(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]RU[Chinese]SZ[19]KM[7.50]TM[14100]OT[5x60 byo-yomi]PW[Gu Li]PB[Lee Sedol]WR[9d]BR[9d]DT[2014-05-25]EV[MLily Gu vs Lee Jubango]RO[Game 5]PC[Shangri-La, Yunnan, China]SO[http://gogameguru.com/]AN[An Younggil 8p]C[This is game 5 of the MLily Gu vs Lee Jubango, between Lee Sedol 9p and Gu Li 9p.The mood of the series changed dramatically when Gu Li defeated Lee Sedol in four consecutive games - including in games 3 and 4 of this match - and the overall score for the Jubango became 2-2.This game was very important for Lee, because if he lost he'd face a heavy burden. It would be very difficult for him to overcome the psychological damage of losing five games in a row, while also being behind in this match.This game was played on May 25, 2014, in Shangri-La, Yunnan. Shangri-La is a famous location in the Chinese highlands, on the Tibetan Plateau.Let's have a look at the game 5 of the match between Lee Sedol 9p and Gu Li 9p.Lee Sedol plays Black.]RE[B+Resign];B[pd];W[dd];B[pq];W[dp];B[qk]LB[dd:2][pd:1][qk:5][dp:4][pq:3]C[Lee started the game with the Chinese Opening.](;W[fq]LB[fq:6]C[The knight's enclosure at White 6 is Gu's favorite move against the Chinese Opening.];B[nc](;W[fc]LB[fc:8][nc:7]C[Enclosing a second corner with White 8 may look strange, but it's quite a common move in this opening.];B[cj];W[cl](;B[cf]LB[cf:11][cg:A][cj:9][cl:10]C[Approaching here was quite active, compared to the possible two space extension at A.](;W[mp]LB[nc:B][jd:A][mp:12]C[Playing at the bottom is bigger and more valuable than extending to A at the top. That's because the space at the bottom is wider and Black has already closed the corner and created a solid position at B in the top right.];B[po];W[jp](;B[ej](;W[re]LB[qc:A][re:16][qh:B][ej:15][po:13][jp:14]TR[nc][pd]C[The low knight's approach at White 16 is the most common technique for dealing with a star point knight's enclosure (e.g. the marked stones). At a fundamental level, it makes miai of entering the corner with A and extending along the side around B.](;B[qd]LB[qd:17][rd:A]C[This move is also quite common, but it was somewhat questionable in this opening. Attaching at A would have been better for Black.](;W[qh]LB[rc:B][rd:C][qf:A][qh:18]C[If White plays another move around A, he can jump into the corner at B later. That's why Gu omitted to push at C in this case.];B[oh](;W[pj]LB[rd:A][oh:19][pj:20]C[White 20 move was a good response to the capping play at Black 19.If Black plays 19 at A, White will just jump to 19 and the result is ok for White.](;B[pk]LB[pk:21]C[Pushing up at Black 21 was the right move order.](;W[qj]LB[qj:22]C[It's not easy to think of this kind of move, but White 22 was the proper move in this game.];B[oj];W[rk];B[rl];W[rj](;B[qm]LB[oj:23][rj:26][rk:24][rl:25][qm:27]TR[pk][qk][po][pq]C[Defending with Black 27 was necessary, but Black's lower right position looks a bit over-concentrated now.];W[qf](;B[hc]LB[hc:29][qd:A][rd:B][qf:28]C[The result up to White 28 was slightly better for White. There weren't any visible mistakes by Lee, which is why I think Black A wasn't the proper move in this game. As I said earlier, it should have been at B instead.](;W[of]LB[of:30]C[The point at 30 and the top were miai, so when Black played at Black 29, White jumped to White 30.](;B[bd]LB[bd:31]C[Sliding with Black 31 was the proper move in this game.];W[cc](;B[mf]LB[cc:32][mf:33][of:A]C[Capping at Black 33 was a mistake.];W[df];B[dg];W[ef](;B[jd]LB[id:B][jd:37][ce:A][df:34][ef:36][dg:35]C[White 34 and 36 were good moves, which made miai of A and B.Black 37 would usually be the last move that Lee would play, but he chose a safe move in this case. Lee's play throughout this match has been fairly careful and reserved so far.];W[ce](;B[cn]LB[ce:38][cn:39]C[Now was the right time to invade at Black 39. Continuing to play in the top left would be too slow.];W[dn];B[do](;W[eo]LB[dn:40][do:41][eo:42]TR[cl][dp]C[The shape in the lower left corner comes up quite often in games and White 42 is the right answer in most cases.];B[co](;W[cp]LB[co:43][cp:44]C[Defending the corner with White 44 was the right decision.](;B[bp]LB[bp:45]C[Lee chose to complicate the game with Black 45, because he was behind.];W[bq];B[ep](;W[bo]LB[bo:48][ep:47][bq:46]C[Cutting at White 48 was the strongest and best response for White.](;B[fp]LB[fp:49]C[Extending to Black 49 was the only move for Black.];W[eq];B[gq](;W[en]LB[en:52][eq:50][gq:51]C[Connecting immediately, at White 52, was good.](;B[dq]LB[dq:53]C[Cutting at 53 was the right move. The moves in this area followed a single path.];W[cq];B[dr];W[gp];B[fo];W[gr];B[hq](;W[fr]LB[fo:57][gp:56][cq:54][hq:59][dr:55][fr:60][gr:58]C[Black provoked White into thrashing around a bit, by adding a stone to his sacrifice at Black 55. This helped Black to develop his remaining stones at the bottom.This solid connection at White 60 was an important move and is worth taking note of.](;B[ho]LB[fm:E][fn:C][gn:D][go:B][ho:61][hp:A]TR[dn][en][eo]C[Feinting a net with Black 16 was a nice haengma which occupied a vital point. If Black ataris at either A or B instead, White can move out and it will be very hard for Black to manage the situation.If we look at Black 61 from an intensely local perspective, Black's net doesn't work because White can escape with the atari at B. However, if White exchanges B to E, his marked stones will be damaged in the process. As we'll see in a moment, this is part of Black's ploy.](;W[iq]LB[hp:A][iq:62][hr:B]C[The diagonal attachment at White 62 was a tesuji for connecting. It made miai of A and B.];B[bn];W[ap](;B[bl]LB[bl:65][bn:63][go:A][ap:64][hp:B]C[Lee chose to omit playing A or B for the time being and connected under with Black 65 on the left side. Playing like this keeps Black's options open for later - Black can choose between A and B based on how White plays on the left side.](;W[go]LB[bl:A][go:66]C[Since Black didn't play at the bottom, and attached at A instead, this atari became a reasonable move for White. The explanation for why is rather subtle, and we'll come to that in a moment.];B[fn];W[gn];B[fm];W[gm];B[fl];W[gl](;B[fk]LB[fk:73][fl:71][gl:72][fm:69][gm:70][fn:67][gn:68]C[The moves from White 66 up to Black 73 followed a single path.](;W[op];B[pp](;W[cg]LB[cg:76][op:74][pp:75]C[Cutting at White 76 was very big. It was worth more than 25 points.];B[hp]LB[hp:77]C[Since White took a big point with White 76, Black set his stones in motion with Black 77. These two points can be regarded as miai and this was the first crucial moment in the game.](;W[hr]LB[in:A][hr:78]C[Defending at White 78 was unavoidable, because trying to capture Black with A doesn't work.](;B[in]LB[im:A][in:79]C[The diagonal move at Black 79 was a bit heavy. Playing at A would have been lighter and better.](;W[il]LB[il:80]C[White's jump at White 80 was a nice and calm move.](;B[ko]LB[ko:81]C[Black's knight's move at Black 81 looked nice and sharp, but Gu's next move made it bad.](;W[jm]LB[jm:82]C[The diagonal move at White 82 was an unexpectedly good move.](;B[ln]LB[jm:A][ln:83]C[Black 83 was the right response to White A, but Black's shape still isn't that nice.](;W[lm]LB[jm:A][lm:84]C[This attachment was a nice followup in combination with A.](;B[km]LB[km:85]C[Wedging with Black 85 was the right move. Every single move the two masters played around here was profound and subtle.];W[kl];B[kn];W[mn](;B[mo]LB[kl:86][kn:87][mn:88][mo:89]C[Wedging with Black 89 was good style.](;W[ll]LB[ll:90]C[The connection at White 90 was the right response.];B[nn];W[mm];B[np];W[lp];B[lo](;W[io]LB[mm:92][hn:A][jn:B][nn:91][io:96][lo:95][lp:94][np:93]TR[ho][hp][gq][hq]C[White 96 was the right move to capture the marked stones. A and B are miai for White.];B[kp];W[kq];B[lq];W[mq];B[lr](;W[kr]LB[kp:97][kq:98][lq:99][mq:100][kr:2][lr:1]C[Blocking at White 102 was the right move.];B[mr];W[jn](;B[no]LB[jn:4][no:5][hq:A][mr:3]C[Black 105 looks weird, but it's most efficient move. The result from Black A up to here was successful for White. The game is very close, but it's slightly better for White.];W[rc];B[rd];W[sd];B[qb];W[ke];B[kd];W[gb](;B[hb]LB[gb:12][hb:13][qb:9][rc:6][kd:11][rd:7][sd:8][ke:10]C[Answering at Black 113 was unavoidable. Gu's endgame from White 6 to White 12 was nice and sharp, and White's still in the lead.];W[bh];B[bi](;W[an]LB[bh:14][bi:15][an:16]C[The hane at 116 was a sente endgame move. If White doesn't play there, Black's descent at 116 will be sente later.](;B[am]LB[am:17]C[Black 117 was a move that only Lee Sedol would dare to play. Lee must have felt he was behind, so he tried to make the game complicated. It was actually an overplay, but if you can't punish this sort of overplay it can easily turn into a good move.](;W[mc]LB[mc:18]C[The attachment at White 118 was very sharp. During the match, I felt that it would be very difficult for Lee to manage the situation, and I anticipated that the game would finish soon.];B[md];W[cm];B[ao](;W[nd]LB[mc:A][md:19][nd:22][cm:20][ao:21]C[This crosscut was a nice followup after A, but it wasn't the best move. White missed a good chance to wrap up the game here, and the game became more complicated afterwards. That's exactly what Lee wanted.](;B[bp]LB[nd:A][bp:23]C[There's no way for Black to answer A, because he's short of ko threats.];W[ld];B[me];W[bo];B[jk](;W[lc]LB[lc:28][ld:24][me:25][jk:27][ok:D][jl:B][an:A][bo:26][jo:C]C[The connection at White 128 was a bit too early. White should have played either at A or B instead. In that case, Black would be forced to cut at C for his next ko threat, and the resulting shortage of liberties would leave behind aji for cutting at D later.We'll come back to look at cutting at D in a moment.];B[nb];W[le];B[bp](;W[if]LB[nb:29][le:30][if:32][bp:31]C[White 132 was too gentle. Gu might have thought the game was already good enough for him, and he was right. The game was still favorable for Gu, but it became more complicated and difficult to finish.];B[aq];W[od](;B[oc]LB[oc:35][od:34][aq:33]C[It was a great relief for Black to be able to win the ko with Black 133. Black 135 was the right way to defend in the top right.];W[nf];B[jl];W[nj];B[oi](;W[rb]LB[rb:40][nf:36][mh:A][oi:39][nj:38][jl:37]C[White 138 was a well timed probe, but White 140 was a mistake. White should have continued at A immediately.];B[lg](;W[pb]LB[pb:42][lg:41]TR[nb][qb][nc][oc][pd][qd][rd]C[Black 141 was an excellent multipurpose move and White 142 was a very nice counter. However, Gu Li didn't followup properly, so White 142 wasn't used to its full potential in the game.];B[je];W[jf];B[kf](;W[kb]LB[kb:46][pb:A][je:43][jf:44][kf:45]C[The diagonal move at White 146 was questionable and it made White A bad.];B[ng](;W[mb]LB[mb:48][ng:47]C[White 148 was necessary in order to capture Black's corner group, but there's still some bad aji in the corner.];B[qe](;W[pe]LB[pe:50][qe:49][pf:A][rf:B]C[Playing at A, instead of White 150, would also be possible. However, there's still some bad aji in the corner either way. Since Black can live small after cutting at B, the game was reversed here.](;B[gc]LB[gc:51][rf:A]C[Black can live in the corner with A, but Lee started to move his group out first with Black 151.];W[fb];B[gf](;W[mh]LB[fb:52][gf:53][mh:54]C[The peep at White 154 was another sharp move.](;B[lf]LB[lf:55]C[Black 55 was a mistake. Lee wanted to fill White's liberties, but this was too much. Gu has a nice chance to catch up again now.];W[ji];B[lh](;W[pc]LB[pc:58][lh:57][ji:56][jo:A]C[White's cut at White 158 was the losing move. Gu just missed a very nice chance to catch up.];B[ih];W[ii];B[jo];W[hn];B[im](;W[hh]LB[hh:64][ih:59][ii:60][im:63][hn:62][jo:61]C[Black 161 and Black 163 were really good and thick moves. After this, Black didn't have any weaknesses to worry about. Defending in gote at 164 was necessary, which was bad news for White.];B[fg];W[he];B[ge](;W[jh]LB[ge:67][he:66][fg:65][jh:68]C[White's atari at White 168 was also necessary.];B[kj];W[eg];B[fh];W[gd];B[ne];W[oe];B[og];W[pf];B[fd];W[hd];B[fe];W[ks];B[ah](;W[ci]LB[fd:77][gd:72][hd:78][fe:79][ne:73][oe:74][pf:76][eg:70][og:75][ah:81][fh:71][ci:82][kj:69][ks:80]C[Black eventually completed his center territory with Black 169. The endgame started here, but after White 172, Black was leading by 13~14 points on the board.It was too late for White to reverse the game now, because Black was too thick everywhere.Nevertheless, White fought on and resisted Black's plans with White 182.];B[di];W[dh](;B[ch]LB[ch:85][dh:84][di:83]C[Even though Black was winning, he couldn't afford to relax yet. Black had to fight back with Black 185 to cement his win.];W[ar];B[ap];W[ci];B[ec];W[eb];B[ch];W[li];B[ki];W[ci];B[ed](;W[dc]LB[eb:90][dc:96][ec:89][ed:95][ch:91][ci:94][ki:93][li:92][ap:87][ar:86]C[Black 195 was a ko threat and White had to defend with White 196.];B[ch];W[kh];B[mg];W[ci];B[hf];W[ie];B[ch];W[jj](;B[kk]LB[ie:2][hf:1][mg:99][ch:3][kh:98][ci:200][jj:4][kk:5]C[The ko fight continued and Black had to defend at Black 205.];W[ci];B[jq];W[jr];B[ch];W[sl];B[sm];W[ci];B[eh](;W[ok]LB[ch:9][eh:13][ci:12][ok:14][sl:10][sm:11][jq:7][jr:8]C[At this stage, Gu was looking for a place to resign. Gu already knew that this cut wasn't a ko threat, but he didn't have enough threats to win the ko anyway.];B[bg];W[ol];B[mk];W[mj];B[nk];W[lk];B[lj];W[nl](;B[mi]LB[eb:190][fb:152][gb:112][hb:113][kb:146][mb:148][nb:129][pb:142][qb:109][rb:140][cc:32][dc:196][ec:189][fc:8][gc:151][hc:29][lc:128][mc:118][nc:7][oc:135][pc:158][rc:106][bd:31][dd:2][ed:195][fd:177][gd:172][hd:178][jd:37][kd:111][ld:124][md:119][nd:122][od:134][pd:1][qd:17][rd:107][sd:108][ce:38][fe:179][ge:167][he:166][ie:202][je:143][ke:110][le:130][me:125][ne:173][oe:174][pe:150][qe:149][re:16][cf:11][df:34][ef:36][gf:153][hf:201][if:132][jf:144][kf:145][lf:155][mf:33][nf:136][of:30][pf:176][qf:28][bg:215][cg:76][dg:35][eg:170][fg:165][lg:141][mg:199][ng:147][og:175][ah:181][bh:114][ch:209][dh:184][eh:213][fh:171][hh:164][ih:159][jh:168][kh:198][lh:157][mh:154][oh:19][qh:18][bi:115][ci:212][di:183][ii:160][ji:156][ki:193][li:192][mi:223][oi:139][cj:9][ej:15][jj:204][kj:169][lj:221][mj:218][nj:138][oj:23][pj:20][qj:22][rj:26][fk:73][jk:127][kk:205][lk:220][mk:217][nk:219][ok:214][pk:21][qk:5][rk:24][bl:65][cl:10][fl:71][gl:72][il:80][jl:137][kl:86][ll:90][nl:222][ol:216][rl:25][sl:210][am:117][cm:120][fm:69][gm:70][im:163][jm:82][km:85][lm:84][mm:92][qm:27][sm:211][an:116][bn:63][cn:39][dn:40][en:52][fn:67][gn:68][hn:162][in:79][jn:104][kn:87][ln:83][mn:88][nn:91][ao:121][bo:126][co:43][do:41][eo:42][fo:57][go:66][ho:61][io:96][jo:161][ko:81][lo:95][mo:89][no:105][po:13][ap:187][bp:131][cp:44][dp:4][ep:47][fp:49][gp:56][hp:77][jp:14][kp:97][lp:94][mp:12][np:93][op:74][pp:75][aq:133][bq:46][cq:54][dq:53][eq:50][fq:6][gq:51][hq:59][iq:62][jq:207][kq:98][lq:99][mq:100][pq:3][ar:186][dr:55][fr:60][gr:58][hr:78][jr:208][kr:102][lr:101][mr:103][ks:180]C[Gu Li resigned here.This was a very interesting and exciting game to watch.Gu Li took an early lead with a nice opening, and he maintained his lead for a long time with his sharp moves.The atari at Black 117 was an overplay, and there were several great chances for Gu to finish the game. However he let them slip through his fingers. Black 141 was an excellent move, and Lee's moves in the second half of the game were very tough and powerful.It looks like Gu Li's concentration faded around move 140, and he played number of questionable moves afterwards. He may have been affected by the high altitude in Shangri-La and it was such a pity for him.Lee must have felt a great deal of pressure going into this match, because he'd lost four consecutive games against Gu in the month beforehand. If he'd lost this game, it would have been quite tough for him to change the mood.With this win, Lee took the lead again with a score of 3-2 for the match. The rest of the games in this jubango will be more interesting as a result.On the other hand, this was a very unfortunate loss for Gu. His play in this game was incredible, and he didn't allow Lee any good chances to catch up until he started to make mistakes after the ko fight around Black 117.Gu showed his outstanding strength in the opening and the middle game, and that was very impressive against Lee.It might be difficult for you to follow this game, because it was extremely difficult to understand. So don't worry if you feel that you don't understand the game completely. If you can feel the fighting spirit of the players, and the tension of play, that's good enough.If you have any questions or opinions, please feel free to leave a comment.Thanks,Commented by Younggil An 8p                                                                                                                                                                                                                                                                        http://gogameguru.com/](;W[ql];B[pl];W[pm];B[ql];W[qn];B[sk];W[rn];B[om];W[pn];B[nm];W[ml];B[mk];W[nk];B[ni]LB[ni:37][mk:35][nk:36][sk:29][ml:34][pl:25][ql:27][nm:33][om:31][pm:26][pn:32][qn:28][rn:30]C[Even if White throws in and squeezes up to White 28, it still doesn't work. After White 30, Black can cut with 31 and win the capturing race, so Gu resigned after move 223 in the game.])(;W[ml];B[pm]LB[ml:1][pm:2]C[If White simply captures at White 1, Black can defend at Black 2 and White can't make two eyes.]))(;B[pm];W[mi];B[nm];W[ml];B[om];W[kg];B[pl];W[pi];B[nh];W[pg]LB[kg:6][pg:10][nh:9][mi:2][pi:8][ml:4][pl:7][nm:3][om:5][pm:1]C[If Black defends at Black 1 (instead of 2), White can win the capturing race after connecting at White 2.]))(;W[bj];B[ch];W[nq];B[bg];W[nr];B[or];W[ls];B[oq];W[ms];B[bf]LB[bf:10][bg:4][ch:2][bj:1][nq:3][oq:8][nr:5][or:6][ls:7][ms:9]C[White doesn't have enough ko threats to cut at White 1. White 3 is a ko threat, but Black can ignore it and he doesn't lose any points up to Black 10.]))(;B[bg];W[kk];B[lj];W[mi]LB[bg:1][mi:4][lj:3][kk:2]TR[ki][kj]C[If Black eliminates the ko with Black 1, White will reverse the game with White 2 and White 4. This would be a disaster for Black.]))(;W[ch];B[dc];W[db];B[cd];W[bc];B[de]LB[db:3][bc:5][dc:2][cd:4][de:6][ch:1]C[If White tries to finish the ko, Black can destroy White's corner up to Black 6.]))(;B[bj];W[ei];B[dj];W[fi];B[gi];W[gj]LB[ei:2][fi:4][gi:5][bj:1][dj:3][gj:6]TR[fd][fe][ge][gf][fg][fh]C[Black shouldn't fall back at Black 1. White will counter-attack up to White 6 and Black's marked stones will be captured.]))(;W[ag];B[ch];W[bg];B[dh];W[ai];B[aj]LB[ag:1][bg:3][ch:2][dh:4][ai:5][aj:6]C[If White just answers at White 1, Black will play Black 2 to Black 6. Now Black's winning by about 15 points on the board.]))(;W[kj];B[jh];W[hg];B[hi]LB[hg:3][jh:2][hi:4][kj:1]C[If White tries to connect with White 1 now, Black can still capture White's center stones with Black 2 and Black 4.]))(;W[kj];B[jh];W[hj];B[gk];W[hl];B[hk];W[ik];B[jj]LB[jh:2][ki:B][hj:3][ij:A][jj:8][kj:1][gk:4][hk:6][ik:7][hl:5][hm:C]C[White can't connect his center stones anymore. A and B are miai for Black.Instead of White 5, if White blocks at 6, Black can double atari with the throw in at 5 (White can't capture at C because it's a snapback).]))(;W[jo](;B[jh];W[ih];B[ii];W[ij];B[hi];W[jj];B[hf];W[pc]LB[pc:9][hf:8][ih:3][jh:2][hi:6][ii:4][ij:5][jj:7][jo:1]TR[jm][jn]C[White should have saved the marked stones with White 1. If Black plays Black 2 to Black 8, the game would be very close after White 9.])(;B[ki];W[jj](;B[kk];W[kj];B[lk];W[lj]LB[ki:2][jj:3][kj:5][lj:7][kk:4][lk:6][jo:1]C[Black 2 doesn't work, because White break through with White 3 to White 7.])(;B[kj];W[kk];B[ik];W[hj]LB[ki:2][hj:7][jj:3][kj:4][ik:6][kk:5][jo:1]TR[jk][jl]C[Blocking at Black 4 doesn't work either. White can capture Black's three stones with this net at White 7.]))(;B[kj];W[ki];B[li];W[lj];B[lk];W[kk];B[jj];W[mk];B[ij];W[mi];B[mg];W[nl]LB[mg:12][ki:3][li:4][mi:11][ij:10][jj:8][kj:2][lj:5][kk:7][lk:6][mk:9][nl:13][jo:1]C[Black 2 and Black 4 don't work very well. White 5 and White 7 are nice responses, and White can live on the inside up to White 13. This variation is a great success for White.])))(;B[mg];W[ji]LB[mg:1][ji:2]TR[mh];B[jo];W[hn];B[im]LB[mg:1][ji:2][im:5][hn:4][jo:3]C[Black should have just connected at Black 1. The game was already reversed, and Black's winning now.])(;B[lh];W[lf]LB[lf:2][kg:B][mg:A][lh:1]C[If Black pushes at Black 1, White can atari at White 2. A and B are miai next.]))(;W[gg];B[fg];W[ff];B[hg];W[ge];B[gh];W[hf];B[rf]LB[ge:5][ff:3][hf:7][rf:8][fg:2][gg:1][hg:4][jg:A][gh:6][jo:B]C[If White tries to capture Black's top group with White 1, Black will be happy to sacrifice it in sente. Black can still come back and live with Black 8 next. Instead of Black 8, A or B are also good continuations.]))(;B[rf](;W[pc];B[se](;W[qc];B[sc];W[qg];B[rg];W[rh];B[sg]LB[pc:2][qc:4][sc:5][se:3][rf:1][qg:6][rg:7][sg:9][rh:8]C[Black can live in the corner through to Black 9 whenever he wants. This is frustrating for White, because he's already spent several moves reinforcing this area.])(;W[qg];B[qc];W[qa];B[sc];W[na];B[rg];W[rh];B[sg]LB[na:8][qa:6][pc:2][qc:5][sc:7][se:3][rf:1][qg:4][rg:9][sg:11][rh:10]C[Even if White omits the atari at 5, Black can still live up to Black 11.]))(;W[se];B[ne];W[oe];B[og];W[pf];B[qg]LB[ne:3][oe:4][se:2][pf:6][rf:1][og:5][qg:7]C[White can't connect at White 2, because Black can capture everything up to Black 7.])))(;W[pf](;B[pc](;W[qc];B[rf];W[se];B[rg];W[qg];B[sc];W[sb];B[sf];W[sc];B[na](;W[qa];B[jb];W[kc];B[jc];W[la];B[gc];W[fb];B[gf]LB[la:16][na:11][qa:12][fb:18][jb:13][sb:9][gc:17][jc:15][kc:14][pc:2][qc:3][sc:8][se:5][gf:19][pf:1][rf:4][sf:10][qg:7][rg:6]C[Defending at White 1 is also conceivable, but then Black 11 is in sente. Because of that, Black can play Black 13 to Black 17 in sente too, before moving out with Black 19. Black would be happy with this development.])(;W[jb];B[pa];W[qa];B[ob];W[oa]LB[na:11][oa:16][pa:13][qa:14][jb:12][ob:15][sb:9][pc:2][qc:3][sc:8][se:5][pf:1][rf:4][sf:10][qg:7][rg:6]C[If White resists with White 12, Black can create a ko fight up to White 16. This is a picnic ko for Black.]))(;W[jb];B[rf];W[se];B[rg];W[qg];B[qc](;W[rh];B[ra];W[sc];B[sb]LB[ra:10][jb:3][sb:12][pc:2][qc:8][sc:11][se:5][pf:1][rf:4][qg:7][rg:6][rh:9]C[If White tries to change the timing of White 3, Black can still create a big picnic ko in the corner up to Black 12. White 9 and White 11 can be transposed in this sequence.])(;W[ra];B[sc];W[sb];B[sf];W[sc];B[qa]LB[qa:13][ra:9][jb:3][sb:11][pc:2][qc:8][sc:10][se:5][pf:1][rf:4][sf:12][qg:7][rg:6]C[White 9 doesn't work either, because Black can throw in at Black 10 and win the capturing race.])))(;B[rf];W[pc];B[se];W[na];B[rg];W[ph];B[sc];W[sg];B[rh];W[sh]LB[na:5][pc:3][sc:8][se:4][pf:1][rf:2][rg:6][sg:9][ph:7][rh:10][sh:11]C[Cutting at Black 2 is careless. White can capture the whole Black group after cutting at White 3.]))(;W[rf];B[ne];W[oe];B[pf]LB[ne:2][oe:3][pf:4][rf:1]C[If White just connects at White 1, Black can capture White's stones by a net like this. ]))(;W[pc];B[qc];W[qa];B[ob];W[pa];B[ra];W[sa];B[oa]LB[oa:8][pa:5][qa:3][ra:6][sa:7][ob:4][pc:1][qc:2]TR[pb]C[Cutting at White 1 doesn't work, because Black can capture the cutting stones up to Black 8.]))(;W[lf](;B[lb];W[mb];B[ma];W[kc];B[kb];W[jc];B[jb];W[ic];B[ib];W[kg];B[qc];W[qa](;B[ra];W[sa](;B[sc];W[pc];B[se];W[pe];B[sf];W[qe];B[sd];W[rf];B[rg];W[sh];B[rh];W[si];B[sg];W[qg]LB[ma:4][qa:13][ra:14][sa:15][ib:10][jb:8][kb:6][lb:2][mb:3][ic:9][jc:7][kc:5][pc:17][qc:12][sc:16][sd:22][pe:19][qe:21][se:18][lf:1][rf:23][sf:20][kg:11][qg:29][rg:24][sg:28][rh:26][sh:25][si:27]C[I don't understand why Gu didn't atari at White 1. If Black still tries to save his top groups with Black 2, his whole group will die up to White 29. White 17 is a very good move in the sequence.])(;B[pc];W[sc]LB[ma:4][qa:13][ra:14][sa:15][ib:10][jb:8][kb:6][lb:2][mb:3][ic:9][jc:7][kc:5][pc:16][qc:12][sc:17][lf:1][kg:11]C[Connecting at Black 16 doesn't help, because White 17 makes an eye and Black can't capture any of White's stones.]))(;B[sc];W[pc];B[se];W[pe];B[sf];W[qe];B[sd];W[rf]LB[ma:4][qa:13][ib:10][jb:8][kb:6][lb:2][mb:3][ic:9][jc:7][kc:5][pc:15][qc:12][sc:14][sd:20][pe:17][qe:19][se:16][lf:1][rf:21][sf:18][kg:11]C[Black 14 doesn't improve the situation either.]))(;B[kc];W[lb];B[kg];W[mg];B[gf]LB[lb:3][kc:2][gf:6][lf:1][kg:4][mg:5]C[Black can block at Black 2 in sente in this case, but this is still far better for White than the actual game.])))(;W[je];B[qe];W[rf];B[pf];W[pg];B[og];W[pe];B[ne];W[oe];B[ng];W[pf];B[pb];W[qc];B[oa]LB[oa:13][pb:11][qc:12][je:1][ne:8][oe:9][pe:7][qe:2][pf:4][rf:3][ng:10][og:6][pg:5]C[If White reinforces at White 1, Black can squeeze with Black 2 to Black 10 in sente. Black can live up to Black 13 and White would be upset with this result.])(;W[ng];B[je];W[jf];B[kf];W[lf];B[lb];W[mb];B[ma];W[kc];B[kb];W[jc];B[jb];W[ic];B[id];W[kg];B[ib];W[kf];B[qc]LB[ma:8][ib:16][jb:12][kb:10][lb:6][mb:7][pb:A][ic:13][jc:11][kc:9][qc:17][id:14][je:2][jf:3][kf:4][lf:5][kg:15][ng:1]C[If White just tries to break into the center with White 1, Black 2 to Black 6 is a brilliant combination. Black can miraculously save both his groups up to Black 17 and White 1 turns out to be small. If this happened, the game would be reversed in Black's favor.When I was watching the game, I thought A (142 in the actual game) was brilliant counter, which prevented this sequence from working. However, Gu chose a different path in the game.]))(;W[mh];B[rb];W[jo]LB[rb:2][mh:1][ok:A][jo:3]TR[jk][jl]C[White should have played in the center with White 1. Black 2 and White 3 are miai next, and the game would still have been favorable for Gu. Remember that White can also aim to cut at A after filling Black's liberties with White 3.]))(;B[oe];W[ne];B[nf];W[pe];B[oc];W[oe];B[og];W[qe];B[jl];W[mh]LB[oc:5][ne:2][oe:6][pe:4][qe:8][nf:3][og:7][mh:10][jl:9]TR[md][me][mf]C[Black 1 is also conceivable, but White can strike at the vital point with White 10. It's better for Black if he doesn't fill his own liberties like this.]))(;W[od];B[oc];W[bo]LB[oc:2][od:1][bo:3]C[White still should have fought the ko like this.]))(;W[an];B[jo];W[hn];B[ao];W[lc];B[nb];W[an];B[bm];W[le];B[ao];W[if]LB[nb:6][lc:5][le:9][if:11][bm:8][an:7][hn:3][ao:10][jo:2]C[White should have taken the ko first. If Black has to connect at Black 8, White can save one move. This can be difficult to understand, but if you compare this to the result in the actual game, you'll see that if Black had a stone at Black 8, it would end up as a wasted move in the end.])(;W[jl];B[bp];W[lc](;B[nb];W[bo];B[jo];W[hn];B[bp];W[le];B[aq];W[od];B[oc];W[nf]LB[nb:4][lc:3][oc:11][od:10][le:8][nf:12][ok:A][jl:1][hn:7][bo:5][jo:6][bp:2][aq:9][nq:B][nr:C]C[Just answering at White 1 would have been alright too. In this case, Black should exchange Black 6 for White 7, and it exposes Black's cutting at A for later.];B[rb];W[nq];B[nr];W[ok];B[nk];W[ol];B[nl];W[nm];B[om];W[on]LB[rb:14][nk:18][ok:17][nl:20][ol:19][nm:21][om:22][on:23][jo:A][nq:15][nr:16]C[After Black loses his liberty at A, cutting at White 17 becomes possible.For example, if Black defends the top right corner with Black 14, White can exchange White 15 for Black 16, before cutting at White 17. Trying to capture with Black 18 to Black 22 doesn't work, because White 23 is double atari.])(;B[le];W[oc];B[nb];W[ob]LB[nb:6][ob:7][lc:3][nc:A][oc:5][le:4][jl:1][bp:2]C[If Black cuts at Black 4 in this sequence, White can simply capture Black A with White 5 and White 7.])(;B[aq];W[oc];B[nb];W[ob];B[ne];W[od];B[oe];W[je]LB[nb:6][ob:7][lc:3][nc:A][oc:5][od:9][je:11][ne:8][oe:10][pe:B][jl:1][bp:2][aq:4]TR[hb][hc][jd][kd]C[If Black doesn't answer White 3, White can capture Black A in sente like this. There's still cutting point at B for later too.])))(;B[ne];W[an];B[bm];W[bk];B[ao];W[ld];B[od];W[an];B[qe];W[al];B[rf];W[gi]LB[ld:6][od:7][ne:1][qe:8][se:B][rf:10][rg:A][ph:C][gi:11][bk:4][al:9][bm:3][an:2][ao:5]C[If Black answers at Black 1, White can continue the ko fight up to White 4. The trade up to White 11 is very good for White.]))(;W[bm];B[bp];W[al](;B[dm];W[an](;B[em];W[bo]LB[al:3][bm:1][dm:4][em:6][an:5][bo:7][bp:2]C[This sequence would be easiest way for Gu to win the game. White 3 is a nice tesuji.])(;B[aq];W[bo]LB[al:3][bm:1][dm:4][an:5][bo:7][bp:2][aq:6]C[Capturing at Black 6 doesn't work.]))(;B[aq];W[an](;B[jo];W[bo];B[ip];W[hj]LB[hj:9][al:3][bm:1][an:5][bo:7][jo:6][bp:2][ip:8][aq:4]TR[dg][bi][cj][ej][fk][fl][fm][fn][fo][ep][fp]C[There are no ko threats for Black (which are big enough). Black 6 and Black 8 don't gain enough compensation and Black's marked stones become very weak.])(;B[qe];W[bo];B[rf];W[gi]LB[qe:6][se:B][rf:8][rg:A][ph:C][gi:9][al:3][bm:1][an:5][bo:7][bp:2][aq:4]TR[dg][bi][cj][ej][fk][fl][fm][fn][fo][ep][fp]C[Black 6 and Black 8 aren't big enough either. White can still save his group by playing A to C later and White 9 attacks Black's weak group even more severely.])(;B[ch];W[bo];B[bg];W[bf];B[cg];W[be]LB[be:11][bf:9][bg:8][cg:10][ch:6][al:3][bm:1][an:5][bo:7][bp:2][aq:4]C[Black can help his group with Black 6 and Black 8, but it's still not good enough.]))(;B[ak];W[bo];B[jo];W[an];B[ip];W[hj]LB[hj:9][ak:4][al:3][bm:1][an:7][bo:5][jo:6][bp:2][ip:8]C[Even if Black captures with Black 4, the result will still be similar to the other variations.])))(;W[ao];B[bk]LB[bk:2][ao:1]C[If White just answers at White 1, Black will be happy to answer at Black 2. Black can save a few points here, and those few points are very important in this close game.]))(;B[bm];W[bk];B[ck];W[le]LB[le:4][bk:2][ck:3][bm:1]C[If Black answers at Black 1, which is the right move, it will still be very close game, though White is slightly ahead.]))(;W[dh];B[if];W[bk];B[bm];W[ck];B[bj];W[al];B[dm];W[an]LB[if:2][dh:1][bj:6][bk:3][ck:5][al:7][bm:4][dm:8][an:9]C[White could also atari at White 1. After that, White's aji around White 3 is rekindled and White can aim to play White 3 to White 9 later.]))(;B[ch];W[bf];B[bh];W[hb];B[ib];W[jb]LB[ia:B][hb:4][ib:5][jb:6][ic:A][bf:2][bh:3][ch:1]C[If Black doesn't answer at the top, White 6 is annoying for Black. A and B are miai next.]))(;B[rd];W[nq];B[no];W[nr]LB[rd:1][no:3][nq:2][nr:4]C[If Black plays elsewhere, White will revive his dead stones with White 2 and White 4.]))(;W[mr];B[kr];W[jq];B[nq]LB[jq:3][nq:4][kr:2][mr:1]TR[lp][mp][mq]C[Even if White blocks on the other side with White 1, Black can still capture the marked stones after atari at Black 2.]))(;W[nq];B[no];W[io];B[kp];W[kq];B[lq];W[mq];B[lr](;W[kr];B[hn];W[jn];B[jo];W[ip];B[ir]LB[hn:10][jn:11][io:3][jo:12][no:2][ip:13][kp:4][jq:A][kq:5][lq:6][mq:7][nq:1][ir:14][kr:9][lr:8][ks:B]C[The atari at White 1 doesn't help in this situation. Black can connect at Black 10 after exchanging Black 4 to White 9. White 11 and White 13 don't work.])(;W[hn];B[jr];W[jq];B[kr]LB[hn:9][io:3][no:2][kp:4][jq:11][kq:5][lq:6][mq:7][nq:1][jr:10][kr:12][lr:8]TR[lp][mp][op]C[If White realizes that Black can escape and come backs to defend at White 9, Black would have no mercy with Black 10 and 12 and White's marked stones are captured.])))(;W[mm];B[no]LB[ll:A][mm:1][no:2]C[White 1 is wrong, because it leaves behind a cutting point at A.]))(;B[mm];W[ll];B[mo];W[nn];B[no];W[lp](;B[lo];W[io]LB[ll:2][mm:1][nn:4][io:8][lo:7][mo:3][no:5][lp:6]TR[ho][hp][gq][hq]C[Cutting at Black 1 is what Gu wanted. White can play at White 6 in sente, and capture the marked stones with White 8.])(;B[nm];W[on];B[oo];W[io]LB[ll:2][mm:1][nm:7][nn:4][on:8][io:10][mo:3][no:5][oo:9][lp:6]TR[ho][hp][gq][hq]C[Even if Black captures White's three stones with Black 7 and Black 9, White's still happy to capture the key stones with White 10.])))(;B[mm];W[kn];B[lo];W[jo]LB[mm:1][kn:2][jo:4][lo:3];B[kq];W[kp];B[lp];W[lq];B[mq];W[lr]LB[mm:1][kn:2][jo:4][lo:3][kp:6][lp:7][np:A][kq:5][lq:8][mq:9][lr:10]TR[mp][op]C[If Black carelessly hanes at Black 1, White can now play at White 2. Even if Black captures the marked stones with A, it's not enough compensation.])(;B[mn];W[lq];B[jo];W[gk];B[gj];W[hj];B[gi];W[hi];B[hh];W[ji]LB[hh:9][gi:7][hi:8][ji:10][gj:5][hj:6][gk:4][mn:1][jo:3][lq:2]C[If Black just extends to Black 1, White will reinforce his lower side with White 2. The result up to White 10 is satisfactory for White. ]))(;W[kp];B[mo]LB[mo:2][kp:1]C[If White just defends at White 1, Black's happy to make a good shape in the center with the attachment at Black 2.])(;W[io];B[lq];W[lp];B[kp];W[kq];B[kr];W[jq];B[mq]LB[hn:A][io:1][kp:4][lp:3][jq:7][kq:5][lq:2][mq:8][kr:6]TR[ho][hp][mp][op][gq][hq]C[If White tries to capture the marked stones, Black can invade at Black 2, and the result up to Black 8 is successful for Black. Black can even try to save the marked stones with A later, because White's short of liberties.])(;W[kn];B[lp];W[jo];B[km];W[jn];B[lq]LB[km:4][jn:5][kn:1][jo:3][lp:2][lq:6]TR[in][ho][hp][mp][op][gq][hq]C[White 1 is a very severe move, which allows White to capture the marked stones. However, White will lose more points than he gains up to Black 6.]))(;B[jo];W[ln]LB[ln:2][jo:1]C[Black 1 is too naive. White can capture Black with White 2, and there's no way to escape.]))(;W[lq];B[jl];W[jk];B[jm];W[ik];B[kk]LB[ik:5][jk:3][kk:6][jl:2][jm:4][lq:1]C[The moves up to Black 6 are what Lee wanted.])(;W[km];B[kn](;W[lm];B[mo]LB[km:1][lm:3][kn:2][mo:4]C[White's knight's attack at White 1 looks severe, but Black 2 is a good way to defend.])(;W[mn];B[lm];W[ln];B[jm];W[kl];B[jl]LB[jl:8][kl:7][jm:6][km:1][lm:4][kn:2][ln:5][mn:3]C[Even if White jumps at White 3, Black can still break through into the center like this.])(;W[io];B[hn];W[jm];B[ip]LB[jm:5][km:1][hn:4][kn:2][io:3][mo:B][ip:6][jq:A]C[If White threatens to cut Black, Black 6 is a nice response. A and B are miai for Black next.])(;W[jm];B[mo];W[io];B[lq];W[lp];B[kp];W[kq];B[kr];W[jq];B[mq];W[np];B[nq]LB[jm:3][km:1][kn:2][io:5][mo:4][kp:8][lp:7][np:13][jq:11][kq:9][lq:6][mq:12][nq:14][kr:10]TR[ho][hp][mp][op][gq][hq]C[White can capture Black's marked stones with White 5, but Black can counter-attack with Black 6 through to Black 14 and White's marked stones are in trouble.]))(;W[kl];B[mo];W[lp];B[lo]LB[kl:1][lo:4][mo:2][lp:3]C[White 1 doesn't apply enough pressure to Black's shape. Black can easily move out and stay connected up to Black 4.]))(;B[jm];W[jl];B[lm]LB[jl:2][jm:1][lm:3]C[This diagonal move at Black 1 looks weak and passive, but it would have been the proper move in this situation.])(;B[jl];W[im];B[jm];W[io]LB[jl:1][im:2][jm:3][io:4]TR[ho][hp][gq][hq]C[If Black attaches at Black 1, White can simply capture the cutting stones with White 2 and White 4.]))(;W[jm](;B[hl];W[gk];B[im];W[jl];B[hk];W[gj];B[hj];W[gi];B[ko]LB[gi:9][gj:7][hj:8][gk:3][hk:6][hl:2][jl:5][im:4][jm:1][io:A][ko:10]C[Capping at White 1 doesn't work well, because Black can grind his way out with Black 2 to Black 8. Even though Black's play in this diagram is bad style, there's no other way out and sometimes you just have to do what's necessary.White's two center stones are in trouble after Black 10.Playing Black 2 at Black 10 immediately looks like better style, but White will block in good shape at 4 and aim to pinch at A next.])(;B[im];W[il];B[jl];W[ik];B[gk];W[hl];B[kn];W[io];B[km];W[hn]LB[gk:6][ik:5][hl:7][il:3][jl:4][im:2][jm:1][km:10][hn:11][jn:A][kn:8][io:9]C[If Black tries to cut and fight directly with Black 2 and Black 4, White will be happy to capture Black's cutting stones, so Black wouldn't play like this. Playing Black 8 at A instead, is better at this point.])))(;B[im];W[hn](;B[lo](;W[io];B[lp];W[lq];B[kq];W[lr];B[mo]LB[im:1][hn:2][in:A][io:4][lo:3][mo:9][lp:5][kq:7][lq:6][lr:8]C[Black 1 and Black 3 are a good combination, and 4 and 5 are miai for Black next. Black 1 is lighter and more flexible than the diagonal move at A. This variation is better for Black than the actual game.])(;W[lp];B[io];W[in];B[jo];W[jn];B[kn];W[jm];B[ll]LB[ll:11][im:1][jm:10][hn:2][in:6][jn:8][kn:9][io:5][jo:7][lo:3][lp:4]C[If White defends at White 4, Black can save his cutting stones with Black 5. The result up to Black 11 is good for Black. White's center group is weak.]))(;B[io];W[in];B[jo];W[jn];B[ko];W[ln];B[lo];W[mo];B[kn];W[km];B[lm];W[mn];B[jm];W[kl];B[hk];W[lp]LB[hk:17][kl:16][im:1][jm:15][km:12][lm:13][hn:2][in:4][jn:6][kn:11][ln:8][mn:14][io:3][jo:5][ko:7][lo:9][mo:10][lp:18]C[If Black just tries to run away with Black 3, White will enclose his group with White 8. Up to White 18, Black's stones are captured.])))(;W[in];B[hr];W[cr];B[ir](;W[jq];B[hn](;W[im];B[hm];W[hl];B[il];W[hk];B[jl]LB[hk:11][hl:9][il:10][jl:12][hm:8][im:7][hn:6][in:1][jq:5][cr:3][hr:2][ir:4]C[If White tries to capture Black with White 1, Black will play Black 2 to Black 12. It's very hard for White to capture these stones and White's in trouble now.](;W[km];B[ij];W[hj];B[hi](;W[ik];B[jk];W[ii];B[jj];W[gi];B[hh];W[gj];B[fh];W[gh];B[gg];W[hg];B[ih];W[fg];B[gf]LB[gf:30][fg:29][gg:26][hg:27][fh:24][gh:25][hh:22][ih:28][gi:21][hi:16][ii:19][gj:23][hj:15][ij:14][jj:20][ik:17][jk:18][km:13]C[Up to Black 24, White's group is trapped and White doesn't have enough liberties to win a capturing race. The moves up to Black 30 show that trying to escape is futile for White.])(;W[gi];B[gj]LB[gi:17][hi:16][gj:18][hj:15][ij:14][km:13]C[If White hanes at White 17, Black can simply cut at Black 18 and White's stones are captured.]))(;W[jm];B[jr];W[lq];B[kr](;W[lr];B[jo](;W[io];B[ij];W[hj];B[hi];W[gi];B[hh];W[gj];B[gh];W[fi];B[fh];W[ei];B[dh](;W[kq];B[ik];W[ks];B[di]LB[dh:30][fh:28][gh:26][hh:24][di:34][ei:29][fi:27][gi:23][hi:22][gj:25][hj:21][ij:20][ik:32][jm:13][io:19][jo:18][kq:31][lq:15][jr:14][kr:16][lr:17][ks:33]C[White 13 is worth considering, but it doesn't work either in this case. White's group will be captured again up to Black 30. You can see that White is losing the capturing race up to Black 34.])(;W[ik];B[jk];W[jj];B[km](;W[ii];B[ip]LB[bf:A][dh:30][fh:28][gh:26][hh:24][ei:29][fi:27][gi:23][hi:22][ii:35][gj:25][hj:21][ij:20][jj:33][ik:31][jk:32][jm:13][km:34][io:19][jo:18][ip:36][lq:15][jr:14][kr:16][lr:17]TR[im][in]C[White can actually escape up to White 35, but only at the expense of his marked stones at the bottom. Up to Black 36, White's lower right group is very weak and his center group is still in trouble. Meanwhile Black has no weaknesses and can look forward to playing the big point at A, after first harassing White's weak groups.])(;W[kn];B[ip];W[jn];B[ln];W[ko];B[ii]LB[dh:30][fh:28][gh:26][hh:24][ei:29][fi:27][gi:23][hi:22][ii:40][gj:25][hj:21][ij:20][jj:33][ik:31][jk:32][jm:13][km:34][jn:37][kn:35][ln:38][io:19][jo:18][ko:39][ip:36][lq:15][jr:14][kr:16][lr:17]C[White might try to resist and setup a ladder with White 35, but Black can defend against the ladder indirectly with Black 36. Up to Black 40, White's still captured.])))(;W[kn];B[kl];W[ij];B[ko];W[ln];B[lo];W[mo];B[mn](;W[lm];B[kq]LB[ij:21][kl:20][jm:13][lm:27][kn:19][ln:23][mn:26][nn:A][jo:18][ko:22][lo:24][mo:25][kq:28][lq:15][jr:14][kr:16][lr:17][ks:B]TR[jp][iq][jq]C[The diagonal move at White 19 doesn't work either. Black 20 hits the vital point and after Black 22, White's shape is too weak to continue the attack. The moves up to White 27 are a one way street and now Black A and B are miai.];W[ks];B[nn];W[ll];B[nr]LB[ll:31][nn:30][nr:32][ks:29]C[If White tries to capture Black with White 29, Black will counter-attack with Black 30 and Black 32. Then White will be the one who is captured.])(;W[io];B[ip];W[lm];B[km];W[jn];B[mm]LB[ij:21][kl:20][jm:13][km:30][lm:29][mm:32][jn:31][kn:19][ln:23][mn:26][io:27][jo:18][ko:22][lo:24][mo:25][ip:28][lq:15][jr:14][kr:16][lr:17]C[If White tries to cut with White 27, Black will cut at Black 28 and White's stones will be captured in a ladder up to Black 32.])))(;W[kl];B[mr];W[nr];B[or];W[lr];B[ls];W[mq];B[ns]LB[jk:B][kl:17][jm:13][lq:15][mq:23][jr:14][kr:16][lr:21][mr:18][nr:19][or:20][gs:A][ls:22][ns:24]C[If White doesn't answer Black 16, Black can create a ko at the bottom up to Black 24. White can't win this ko, because Black has so many ko threats in this area (starting with A and B, for example).]))(;W[ij];B[io](;W[km];B[kn];W[jm];B[jo]LB[ij:13][jm:17][km:15][kn:16][io:14][jo:18]C[If White takes care of his center group with White 13, Black can move out with Black 14. After Black 18, there's no way for White to hold Black in.])(;W[jn];B[jo];W[kn];B[ko];W[ln];B[lq]LB[ij:13][jn:15][kn:17][ln:19][io:14][jo:16][ko:18][lq:20]TR[jp][iq][jq]C[White 15 doesn't work either. Up to Black 20, White's marked stones have been captured and White's outside stones are still very weak.])))(;W[hm];B[io](;W[jo];B[im];W[jn];B[gk]LB[gk:12][hl:A][il:B][hm:7][im:10][hn:6][in:1][jn:11][io:8][jo:9][jq:5][cr:3][hr:2][ir:4]C[If White blocks immediately at White 7, pushing at Black 8 is a nice move and White's stones are captured instead.])(;W[jn];B[jo];W[ko];B[kp](;W[kq];B[kn];W[lo];B[im];W[jm];B[il]LB[gk:A][il:18][hm:7][im:16][jm:17][km:B][hn:6][in:1][jn:9][kn:14][io:8][jo:10][ko:11][lo:15][kp:12][jq:5][kq:13][cr:3][hr:2][ir:4]C[If White extends at White 9, Black can still push through and cut. White's still in deep trouble up to Black 18, because A and B are miai.])(;W[kn];B[kq];W[jr];B[kr]LB[hm:7][hn:6][in:1][jn:9][kn:13][io:8][jo:10][ko:11][kp:12][jq:5][kq:14][cr:3][hr:2][ir:4][jr:15][kr:16]TR[jp][iq]C[If White connects at White 13, Black can capture the White stones at the bottom.]))))(;W[jr];B[hn];W[im];B[hm];W[hl];B[il];W[hk];B[jo](;W[io];B[ip]LB[hk:11][hl:9][il:10][hm:8][im:7][jm:B][hn:6][in:1][io:13][jo:12][ip:14][jq:A][cr:3][hr:2][ir:4][jr:5]C[If White blocks at White 5, Black can play Black 6 to Black 12. White 13 doesn't work, because A and B are miai for Black after Black 14.])(;W[kn];B[kq](;W[jq];B[io];W[ko];B[kp](;W[kr];B[ik];W[hj];B[jn];W[jm];B[km];W[jl];B[lo]LB[hj:21][hk:11][ik:20][hl:9][il:10][jl:25][kl:A][hm:8][im:7][jm:23][km:24][hn:6][in:1][jn:22][kn:13][io:16][jo:12][ko:17][lo:26][kp:18][jq:15][kq:14][cr:3][hr:2][ir:4][jr:5][kr:19]C[White 13 looks nice haengma, but it doesn't still work. Peeping at Black 14 is a good move, and eventually White's stones will be captured. The atari at A is sente for Black at any time.])(;W[jn];B[kr]LB[hk:11][hl:9][il:10][hm:8][im:7][hn:6][in:1][jn:19][kn:13][io:16][jo:12][ko:17][kp:18][jq:15][kq:14][cr:3][hr:2][ir:4][jr:5][kr:20]TR[jp][iq]C[If White connects at White 19, Black can capture White's four stones with Black 20.]))(;W[kp];B[jq];W[lq];B[kr]LB[hk:11][hl:9][il:10][hm:8][im:7][hn:6][in:1][kn:13][jo:12][ip:A][kp:15][jq:16][kq:14][lq:17][cr:3][hr:2][ir:4][jr:5][kr:18][js:B]C[If White answers Black's peep at White 15, Black can simply capture White 5 and live. A and B are miai next.])))))(;W[hp];B[bf]LB[be:A][bf:2][hp:1]C[White's position at the bottom would become very thick and strong after White 1, but it's a bit slow. Black 2 is a very big point.])(;W[jm];B[bf]LB[bf:2][il:A][jm:1][kn:B]TR[ho][gq][hq]C[If White plays here, with the intention of capturing the marked stones on a larger scale, Black will still defend on the left side. Black can aim to reduce White's lower side with A or B later.]))(;W[bm];B[an]LB[am:C][bm:1][cm:A][dm:B][an:2]C[Some readers' eyes might still be drawn to White 1, but Black 2 is a strong response which makes miai of A and B. Rather than losing points with this exchange, White should save this aji for later and hane at 2 instead in the endgame.]))(;B[bf];W[dm]LB[bf:1][fk:A][bm:B][dm:2]C[If Black doesn't defend at A, and takes a big point at Black 1 for example, White 2 is a tesuji. After White 2, A and B are miai, so Black's position on the left side crumbles.]))(;W[gm];B[hp];W[hr];B[jo]LB[gm:1][jo:4][gp:A][hp:2][hr:3]C[If White plays the knight's move at White 1, Black can make a better shape than in the previous variations with Black 2 and Black 4.])(;W[bk];B[go];W[hr];B[dm];W[em];B[dl]LB[bk:1][dl:6][bm:A][cm:B][dm:4][em:5][go:2][hr:3]TR[cl][dn][en][eo]C[If White tries to fight with White 1, Black can exchange Black 2 for White 3 in sente, before moving out up to Black 6. White's marked stones are all in trouble (if White plays A, then B), so this variation isn't good for White.])(;W[bm];B[go];W[hr];B[cm];W[dm];B[an];W[bk];B[dl];W[al];B[fn];W[em];B[el]LB[bk:7][al:9][dl:8][el:12][bm:1][cm:4][dm:5][em:11][an:6][fn:10][go:2][hr:3]C[Since White's decided to sacrifice his stones, he might consider trying to create some ko aji with White 1 first. However, this won't go as planned.Black can resist by exchanging Black 2 for White 3 in sente again. Next, Black takes the vital point with Black 6, which makes miai for White 7 and Black 8. Up to Black 12, White's cutting stones are captured in a ladder.]))(;B[go];W[hr];B[bl];W[el]LB[bk:A][bl:3][el:4][go:1][hr:2]C[If Black exchanges Black 1 for White 2 first, White will make shape with White 4. White can move into the center or start a ko with A next.])(;B[hp];W[hr];B[bl];W[fn];B[go];W[hm]LB[bl:3][hm:6][fn:4][go:5][hp:1][hr:2]C[Capturing the cutting stone with Black 1 is a little bit heavy. White can atari at White 4 and attack with White 6 next. Lee didn't like this prospect.]))(;W[go];B[fn];W[gn];B[fm];W[bn];B[hr];W[cr];B[hp]LB[fm:4][bn:5][fn:2][gn:3][go:1][hp:8][cr:7][hr:6]C[Moving the cutting stone out with White 1 and White 3 is possible, but it's not good. It's hard for White to manage the three stones after the game proceeds up to Black 8.]))(;B[hr];W[gn];B[go];W[ho];B[hp];W[fn];B[gp];W[cr];B[io];W[hn];B[ip];W[jq]LB[fn:6][gn:2][hn:10][go:3][ho:4][io:9][gp:7][hp:5][ip:11][jq:12][cr:8][hr:1]TR[eq][fq][fr][gr]C[If Black still blocks at Black 1, White can squeeze with White 2 to Black 7 now. This is possible because the marked stones have one more liberty than they did in the previous variation.Up to White 12, Black's group is heavy and is under attack. Even though Black drilled through White's shape with Black 9 and Black 11, Black also made bad shape for himself in the process. We can regard the local shape considerations as a tit for tat exchange, but White 12 occupies a vital point while reinforcing White's group, and White will be happy with the overall development of the game.]))(;W[er];B[hr](;W[cr];B[fn];W[fm];B[ho]LB[fm:5][fn:4][ho:6][gp:A][cr:3][er:1][hr:2]C[Blocking at White 1 looks like the normal technique, but it's wrong in this situation. Now Black can block at Black 2 in sente, and the difference is very big. Black can capture White A in good shape.])(;W[gn];B[es];W[fr];B[gs]LB[fn:D][gn:3][go:A][ho:B][gp:E][hp:C][er:1][fr:5][hr:2][es:4][gs:6]C[White would like to ruin Black's shape with White 3, before defending at the bottom. If Black ataris at A next, White will squeeze in sente with the moves through to E. However, Black 4 is a simple way to resist and Black wins the capturing race with Black 6. So White 3 is an overplay in this case.Notice how this wouldn't have happened if White had simply connected with White 1 at White 5 though (as in the actual game). We'll look at that more closely in a moment.])))(;B[hp];W[ap]LB[ap:2][hp:1][dq:A]TR[cn][co][do]C[Black shouldn't just connect at Black 1, because White 2 will remove the cutting point at A, and capture the marked stones at the same time. Once Black loses his leverage against White's lower left group, his stones at the bottom become heavy and inflexible.]))(;W[gp];B[fo];W[en];B[hp];W[go];B[fn](;W[hq];B[gn];W[gr];B[dm]LB[dm:10][en:3][fn:6][gn:8][fo:2][go:5][gp:1][hp:4][hq:7][gr:9]C[Cutting at White 1 and inducing White 3 is often better technique, but it doesn't work very well in this case. Black 4 is a nice haengma, and Black 10 captures White's cutting stones in a ladder. Black's happy with the result up to Black 10.])(;W[ho];B[io];W[ip];B[dm]LB[dm:10][en:3][fn:6][gn:C][hn:A][fo:2][go:5][ho:7][io:8][gp:1][hp:4][ip:9][hq:B]C[White 7 looks better, but the result is about the same. Black won't have a problem capturing White's three stones in a ladder, because he can squeeze with A to C if he needs to.])))(;B[bn];W[ap];B[en];W[fo];B[dm];W[fn]LB[dm:5][bn:1][en:3][fn:6][bo:A][fo:4][ap:2][fp:B]C[If Black exchanges the atari at Black 1 and then double ataris with Black 3, the result is very different to the previous variation. White has played at A, instead of B, and that makes a huge difference in terms of efficiency, because White saves a move.])(;B[eq];W[fp];B[cq];W[ap];B[dq];W[bp]LB[ap:4][bp:6][fp:2][cq:3][dq:5][eq:1]C[Black 1 doesn't work, because White can block at White 2. After White 6, Black collapses.]))(;W[en];B[eq];W[bo];B[fp]LB[bl:D][bn:B][en:1][bo:3][ap:C][fp:4][cq:A][eq:2]C[If White connects at White 1, Black will break through at the bottom. Black can either squeeze the corner later with A, or save his three stones with B to D.])(;W[fp];B[en];W[fo];B[dm]LB[dm:4][dn:A][en:2][bo:B][fo:3][fp:1][cq:C]C[If White simply captures the cutting stone with White 1, Black will be happy to double atari with Black 2 and capture with Black 4. Connecting at B will also be sente for Black later, because he can aim to play C next.]))(;B[dm];W[en];B[cm];W[em];B[dl];W[nr];B[or];W[op];B[pp];W[oq]LB[dl:5][cm:3][dm:1][em:4][en:2][op:8][pp:9][nq:A][oq:10][nr:6][or:7]C[Black 1 and Black 3 are normal, but then White can close off the bottom and simplify the game with White 6 to White 10. This result is good for White.It's worth noting White 6, which is a more advanced technique for completing White's territory at the bottom (in terms of endgame potential) than simply playing at A.]))(;W[dm];B[cp];W[cq];B[bq];W[dq];B[br]LB[dm:1][en:A][cp:2][bq:4][cq:3][dq:5][br:6]C[Extending at White 1 is wrong in this situation. Black can easily live in the corner, up to Black 6, and White needs to spend one more move to prevent Black from cutting at A.]))(;W[co];B[eo];W[cp];B[dm];W[bn];B[en];W[cm];B[ip];W[iq];B[hq]LB[cm:7][dm:4][bn:5][dn:A][en:6][co:1][eo:2][cp:3][ip:8][hq:10][iq:9]C[White can also consider playing White 1 to White 7, but then Black will bully White on the lower side as well, starting with Black 8 and Black 10. In general, giving up the stone at A isn't a good idea, because this sequence exchanges center influence for a small territory on the edge. And Black gets sente.]))(;B[bf];W[co]LB[bf:1][co:2]C[If Black just defends with Black 1, Gu will be happy to secure the corner with White 2.]))(;B[cg];W[id];B[ic];W[jd];B[hd];W[he](;B[jc];W[kd];B[lb];W[if]LB[lb:9][hc:A][ic:3][jc:7][hd:5][id:2][jd:4][kd:8][he:6][if:10][mf:B][cg:1]C[If Black defends the left side with Black 1, White will press Black B down with White 2 and reduce Black's area at the top. Up to White 10, Black B is practically a wasted move.])(;B[ie];W[hf];B[je];W[jc];B[ke];W[jb]LB[jb:12][ic:3][jc:10][hd:5][id:2][jd:4][he:6][ie:7][je:9][ke:11][hf:8][cg:1]C[Black can't easily cut and fight, with moves like Black 7, because White's position is stronger than Black's. Up to White 12, Black's three stones are more or less captured.]))(;B[he];W[ce]LB[hb:B][jc:A][mc:C][ce:2][he:1][je:D]C[Jumping out at Black 1 is common, but Lee didn't play there. It looks as if he was worried about White's potential invasion at A later on. After invading at A, White has good continuations at B-D, for example. ]))(;B[ef]LB[bc:A][ef:1][mf:B]C[Black should have jumped to Black 1, which makes miai of A and B. The game would still have been alright for Black if he'd jumped here.]))(;B[cc];W[cd];B[bd];W[be];B[bc];W[ce](;B[eb];W[ec];B[fb];W[df];B[gc];W[ch]LB[eb:7][fb:9][bc:5][cc:1][ec:8][gc:11][bd:3][cd:2][be:4][ce:6][df:10][ch:12]TR[cj][ej]C[Invading with Black 1 at 3-3 is also conceivable, but can't be recommended. Black's marked stones become weaker after the moves through to White 12.])(;B[bf];W[dc];B[ae];W[df];B[dg];W[ef]LB[bc:5][cc:1][dc:8][hc:A][bd:3][cd:2][ae:9][be:4][ce:6][bf:7][df:10][ef:12][cg:B][dg:11]C[If Black blocks at Black 7, White can change directions with White 8. The result up to White 12 is playable for White. Black's stone at A is weak now and there's also a cutting point at B.])(;B[dc];W[ec];B[bf];W[ae];B[df];W[hd](;B[id];W[gd]LB[db:A][bc:5][cc:1][dc:7][ec:8][ic:B][bd:3][cd:2][gd:14][hd:12][id:13][ae:10][be:4][ce:6][bf:9][df:11]C[If Black pushes first at Black 7, which is quite aggressive, attaching at White 12 is a nice tesuji. After White 14, A (which captures the corner) and B are miai for White.])(;B[ic];W[db];B[ed];W[ee];B[fd];W[ge]LB[db:14][bc:5][cc:1][dc:7][ec:8][ic:13][bd:3][cd:2][ed:15][fd:17][hd:12][ae:10][be:4][ce:6][ee:16][ge:18][bf:9][df:11]C[Quietly falling back with Black 13 doesn't work well in this case. White can capture the corner with White 14 and, if Black cuts at Black 15 next, White can capture Black's cutting stones with the net up to White 18.Note the role that the exchange of White 12 for Black 13 plays in making this net possible.];B[cb];W[ea];B[de];W[gd];B[ad];W[fe];B[ed];W[fd];B[ab];W[md]LB[ea:20][ab:27][cb:19][ad:23][ed:25][fd:26][gd:22][md:28][de:21][fe:24]TR[hc][ic]C[Some players might worry that Black can still live with Black 19 and Black 21. However, the position is still good for White and up to White 28, Black's marked stones are heavy.])(;B[ed];W[ee];B[fd];W[ge]LB[bc:5][cc:1][dc:7][ec:8][bd:3][cd:2][ed:13][fd:15][hd:12][ae:10][be:4][ce:6][ee:14][ge:16][bf:9][df:11]C[Even if Black cuts immediately with Black 13, the net up to White 16 still works.]))))(;W[bd];B[of]LB[bd:1][of:2]TR[hc][nc][oh][oj]C[If White secures the corner with White 1 instead, Black will come back to Black 2 and develop a nice position at the top.]))(;B[of];W[ic]LB[ic:2][of:1]C[Even though it's a nice place to play, enclosing White with Black 1 is slack. White already has a comfortable position on the right, so sealing him in is ineffective and lacks power. White will be happy to extend to White 2 and reduce Black's influence at the top.]))(;B[qf];W[ql];B[rm];W[ok];B[pl];W[oi];B[nj];W[ni]LB[qf:1][ni:8][oi:6][nj:7][ok:4][pl:5][ql:2][rm:3]C[If Black doesn't reinforce on the right side, White can break through into the center like this.]))(;W[oj];B[qj]LB[oh:A][pi:B][oj:1][qj:2]C[White shouldn't extend to White 1 in this sort of situation. Black 2 occupies the vital point in combination with Black A (an eye stealing tesuji), and connecting at B next will make Black A into an excellent move.]))(;B[qj];W[pi](;B[pk];W[nj];B[ok];W[nh]LB[nh:6][pi:2][nj:4][qj:1][ok:5][pk:3]C[If Black pushes at Black 1 first, White will move into the center like this.])(;B[rg];W[qg](;B[rh];W[qf];B[pk];W[nj];B[ok];W[nh]LB[rc:A][qf:6][qg:4][rg:3][nh:10][rh:5][pi:2][nj:8][qj:1][ok:9][pk:7]C[Black can steal White's eyespace with Black 3 and Black 5, but the result up to White 10 is still playable for White. White will be able to jump into the corner at A later, without any trouble.])(;B[rf];W[qf];B[qe];W[rh];B[rd];W[nj]LB[rd:9][qe:7][qf:6][rf:5][qg:4][rg:3][rh:8][pi:2][nj:10][qj:1][qm:B][pn:A]C[Capturing White's stone isn't a good idea either. White can develop his group with White 10 and aim to follow up with A or B.]))))(;W[rj];B[rk];W[qj];B[pj];W[pi];B[oi]LB[oi:6][pi:5][pj:4][qj:3][rj:1][rk:2]C[Sliding with White 1 isn't a good idea in this situation. Black will be happy to build a nice wall up to Black 6.]))(;W[rd];B[rc];W[rb];B[qc];W[qh]LB[rb:3][qc:4][rc:2][rd:1][qh:5]C[White can also exchange White 1 to Black 4 first, but they're unnecessary and a little heavy in this case. Let's stay focused on the actual game.]))(;B[rd](;W[qe];B[qd];W[qi];B[pg];W[oi];B[ok];W[rg]LB[fc:B][qd:3][rd:1][qe:2][pg:5][rg:8][oi:6][qi:4][cj:A][ok:7]C[Attaching at Black 1 is the most common response. The result up to White 8 is playable for both players and the game would still be even.We saw the same pattern earlier (when White played at A instead of B) and I said that it was better for Black. If you compare the two positions, you'll see that Black's potential at both the top and the bottom is much more limited in this diagram, which is what makes this variation playable now.])(;W[qd];B[qe];W[qc];B[rc];W[pe];B[qf];W[pc];B[od];W[rf];B[rb];W[qg];B[pf];W[og];B[of];W[nf];B[pg];W[ph];B[oe];W[rh];B[qi];W[qh];B[cn]LB[rb:11][pc:8][qc:4][rc:5][od:9][qd:2][rd:1][oe:19][pe:6][qe:3][nf:16][of:15][pf:13][qf:7][rf:10][og:14][pg:17][qg:12][ph:18][qh:22][rh:20][qi:21][cn:23]C[Wedging at White 2 was quite popular until the early 2000s. However, the result through to White 22 is now regarded as better for Black, so it's very rarely seen these days. Black's corner is quite big, and he has sente too.]))(;B[qe];W[rd];B[rf](;W[pc];B[qf];W[oc];B[od];W[nb];B[qc];W[qb](;B[rb];W[mc];B[nd];W[pb]LB[nb:8][pb:14][qb:10][rb:11][mc:12][oc:6][pc:4][qc:9][rc:A][md:B][nd:13][od:7][rd:2][qe:1][qf:5][rf:3]C[If Black plays Black 1 and Black 3, Attaching at White 4 is an interesting move. The result up to White 14 is playable for both. If Black connects at A, White will push up at B.])(;B[mb];W[qd]LB[mb:11][nb:8][qb:10][oc:6][pc:4][qc:9][od:7][qd:12][rd:2][qe:1][qf:5][rf:3]C[If Black double hanes with Black 11, White will cut at White 12 and live in the corner. It's another game.]))(;W[qf];B[qg];W[pf];B[rh];W[pc];B[qc](;W[qd];B[pb];W[pe];B[oc]LB[pb:11][oc:13][pc:8][qc:9][qd:10][rd:2][pe:12][qe:1][pf:6][qf:4][rf:3][qg:5][rh:7]C[If White cuts at White 4 first, Black can play Black 5 to Black 7. If White continues with White 10, Black can play the moves up to Black 13 to attack White's group as a whole. White isn't happy about this weak group.])(;W[qb];B[qd];W[rc];B[pb];W[oc];B[rb];W[od];B[qa];W[ob];B[oe];W[pe];B[qb];W[sb](;B[of];W[pg](;B[og];W[ph];B[nd];W[ra];B[sa];W[qh](;B[nb];W[rg];B[hc]LB[qa:17][ra:27][sa:28][nb:30][ob:18][pb:13][qb:10][rb:15][sb:21][hc:32][oc:14][pc:8][qc:9][rc:12][nd:26][od:16][qd:11][rd:2][oe:19][pe:20][qe:1][of:22][pf:6][qf:4][rf:3][og:24][pg:23][qg:5][rg:31][ph:25][qh:29][rh:7]C[White can hane under at White 10, and a complicated variation would be followed like this. The result up to Black 32 is still even. ])(;B[rg];W[ra]LB[qa:17][ra:27][sa:28][ob:18][pb:13][qb:10][rb:15][sb:21][oc:14][pc:8][qc:9][rc:12][nd:26][od:16][qd:11][rd:2][oe:19][pe:20][qe:1][of:22][pf:6][qf:4][rf:3][og:24][pg:23][qg:5][rg:30][ph:25][qh:29][rh:7]C[Black can't answer the ko threat at Black 30, because there's no big enough ko threat for Black now. ]))(;B[nd];W[ra];B[sa];W[qh];B[nb];W[rg]LB[qa:17][ra:25][sa:26][nb:28][ob:18][pb:13][qb:10][rb:15][sb:21][oc:14][pc:8][qc:9][rc:12][nd:24][od:16][qd:11][rd:2][oe:19][pe:20][qe:1][of:22][pf:6][qf:4][rf:3][og:A][pg:23][qg:5][rg:29][ph:B][qh:27][rh:7]C[If Black doesn't exchange at A and B, White would start the ko right away. This result is favorable for White, because there's no exchange of A and B. ]))(;B[nd];W[ra];B[sa];W[of](;B[sc];W[ne]LB[qa:17][ra:23][sa:24][ob:18][pb:13][qb:10][rb:15][sb:21][oc:14][pc:8][qc:9][rc:12][sc:26][nd:22][od:16][qd:11][rd:2][ne:27][oe:19][pe:20][qe:1][of:25][pf:6][qf:4][rf:3][qg:5][rh:7]C[Black 22 is a mistake. White can start the ko right away, and the result up to White 27 is good for White. ])(;B[ne];W[ra]LB[qa:17][ra:23][sa:24][ob:18][pb:13][qb:10][rb:15][sb:21][oc:14][pc:8][qc:9][rc:12][nd:22][od:16][qd:11][rd:2][ne:26][oe:19][pe:20][qe:1][of:25][pf:6][qf:4][rf:3][qg:5][rh:7]C[Black can't answer at Black 26, because there's no big enough ko threat for Black. ]))))))(;W[ch];B[dg];W[bd];B[dh]LB[bd:3][dg:2][ch:1][dh:4][cn:A]C[White can complete the corner territory by sacrificing a stone at White 1, but Black's group will also become thicker in the process. Black will be able to invade at A easily, later on.]))(;B[qe];W[ce];B[df];W[ch];B[bh];W[bg];B[bf];W[bi];B[dh];W[ci];B[di];W[dj](;B[ed];W[ec];B[de](;W[ej];B[cc];W[jc]LB[cc:17][ec:14][jc:18][cd:C][ed:13][fd:B][ce:2][de:15][qe:1][bf:7][df:3][bg:6][bh:5][ch:4][dh:9][bi:8][ci:10][di:11][dj:12][ej:16][dk:A]TR[cl][dp][jp][mp][fq]C[If Black plays elsewhere - at Black 1 for example - White can attack with White 2 and White 4.Black's group isn't in trouble (locally), because Black 15 makes miai of A and Black 17, but White 16 is also a very good move in this opening. After Black 17 White's developed a very large moyo at the bottom. White can look after his group at the top with White 18, because B is sente (if Black ignores B then C next).])(;W[cd];B[dk];W[ej];B[ck]LB[ec:14][cd:16][ed:13][ce:2][de:15][qe:1][bf:7][df:3][ef:E][ff:F][bg:6][cg:C][dg:A][eg:B][bh:5][ch:4][dh:9][eh:D][bi:8][ci:10][di:11][dj:12][ej:18][ck:19][dk:17]C[If White connects at White 16, Black will counter with Black 17 and Black 19. Cutting at A doesn't work anymore for White, because White's cutting stone will be captured after A-F.]))(;B[dk];W[ej];B[ck];W[dg];B[eg];W[cg];B[eh];W[ef]LB[ce:2][qe:1][bf:7][df:3][ef:20][bg:6][cg:18][dg:16][eg:17][bh:5][ch:4][dh:9][eh:19][bi:8][ci:10][di:11][dj:12][ej:14][ck:15][dk:13]C[It's too early for Black to try to fight with Black 13. White will cut with White 16 and White 20 and Black's in trouble.])))(;W[ch];B[bh];W[bg];B[cg];W[bi];B[bf];W[ci];B[cc]LB[cc:8][bf:6][bg:3][cg:4][bh:2][ch:1][bi:5][ci:7]C[If White invades immediately at White 1, Black will respond with Black 2 to Black 8. There are other possible options for White, so invading at White 1 isn't urgent for Gu. This sequence isn't played very often anymore, because there are other moves, which we'll look at in a moment.]))(;B[cg];W[ce];B[cc];W[np];B[oo]LB[cc:3][ce:2][cg:1][oo:5][np:4]C[This opening was played in game 2 of the 2012 Samsung Cup semifinal, by Gu Li 9p (White) and Park Junghwan 9p. Gu Li won this game by resignation.]))(;W[np];B[po];W[oq];B[pr];W[nn](;B[mo];W[no];B[pm];W[jp];B[fc]LB[fc:10][pm:8][nn:5][mo:6][no:7][po:2][jp:9][np:1][oq:3][pr:4]C[The opening up to Black 10 was quite popular around 2010-2011.])(;B[cj];W[qm];B[pm];W[pl];B[ql];W[pn];B[om];W[on];B[qn];W[rm]LB[cj:6][ol:B][pl:9][ql:10][om:12][pm:8][qm:7][rm:15][nn:5][on:13][pn:11][qn:14][po:2][qo:A][np:1][oq:3][pr:4]C[If Black doesn't reinforce the right side, White can invade at White 7. The result up to White 15 is troublesome for Black, because A and B are miai for White.]))(;W[cj];B[fc];W[df];B[id];W[re];B[rd];W[qe];B[qd];W[qi];B[pg];W[oi];B[ok];W[rg];B[np]LB[fc:2][id:4][qd:8][rd:6][qe:7][re:5][df:3][pg:10][rg:13][oi:11][qi:9][cj:1][ok:12][np:14]C[If White plays on the left side, with White 1, Black will develop the top with Black 2 and Black 4. White 5 to White 9 is normal, but Black 10 is an asking move which is difficult to answer in this case. The opening up to Black 14 is another game, but the result is slightly better for Black.]))(;W[nc];B[pf];W[qc];B[pc];W[pb];B[ob];W[qb];B[oc];W[re];B[rf];W[qe];B[qf];W[nb]LB[nb:13][ob:6][pb:5][qb:7][nc:1][oc:8][pc:4][qc:3][qe:11][re:9][pf:2][qf:12][rf:10]C[The variation from White 1 up to White 13 has been very popular since 2013. It's possible that Gu is tired of seeing this pattern, because it's has been played in many games recently. We discussed this pattern earlier, in the commentary of game 3.]))