(;GM[1]FF[4]SZ[19]AP[SmartGo:3.0.1]CA[utf-8]
GN[AlphaGo_selfplay_09]
PW[AlphaGo]
PB[AlphaGo]
KM[7.5]
RE[B+Resign]
RU[Chinese]ST[2]MU[1]
C[AlphaGo-AlphaGo Game 9
Commentary by Michael Redmond 9P
Edited by Chris Garlock and Myron Souris. 

In this game there's a big fight on the left side involving a ko and a trade. Then there's another ko that doesn't happen. ]
;B[pd];W[dd];B[qp];W[dq];B[do];W[co];B[cn];W[cp];B[dn]
C[AlphaGo in this Ke Jie version plays the solid connection almost every time, while the Lee Sedol version liked to play a hanging connection. In a video Fan Hui showed us what AG plans to do if White plays away (see var). ]
(;W[fq];B[cf]
C[This position on the left side occurred in 7 of the 50 self-played games. Black's corner stones on the right side are different, so this board position happened only once. ]
;W[dj]LB[fc:A][di:B]
C[Looking at the left side only, AlphaGo plays at A or B in other games from the self-played set of 50, so this 3-space pincer is unusual. The position of Black's 2 stones on the right is slightly different in the other games, so that could potentially be a cause for White to choose a different move. ]
;B[fc];W[fd];B[gd];W[fe];B[dc]LB[ec:A][cc:B]
C[Black's attachment at 17 is by far the most common move for AlphaGo to play in this joseki. Occasionally it plays at A with Black, and never at B. A and B are both historically popular moves in human play, but have become less common in recent years, so maybe human pros and AG are in agreement here. I remember that Go Seigen 9P liked to play at 17. ]
;W[cc];B[ec];W[cd];B[ch]TR[dj]
C[Black 21 is AlphaGo's favorite move with this corner shape, and AG plays here even if White doesn't have the marked stone. Black is threatening to connect on the side (see var). ]
(;W[ci]
C[White cuts Black off, hoping to attack the two Black groups. ];B[eh];W[fg]
;B[hd]TR[ed]
C[Black protects the upper side group, threatening to push through at the marked point. With White, I would want to protect the UL group now (see var).  ]
(;W[fo]TR[go]
C[White plays away from the UL corner. Alphago likes to play at the marked point with Black, and White 26 prevents that and attacks Black on the left. ]
;B[gf]
C[There seem to be two fights going on at once, with Black attacking White's group in the UL corner, and White attacking Black on the left side. I would emphasize the UL corner, because White has already played several stones in the LL corner area, and the UL seems to be larger in territory (see var). ]
(;W[fk]TR[be]
C[White plays away from the corner again with 28. If White plays at the marked point the corner will not die unconditionally, so maybe AlphaGo isn't worried about that group. ]
;B[ck]
C[Black starts from the left side. Black 29 creates some possibilities to live on the side, but that is not the only reason for this move. The form of Black's attack against the corner will change depending on how White responds to B29 (see var). ]
(;W[bh]TR[cf][ch][eh]
C[White 30 is the strongest local move. Black is now going to set up a ko, using White's counter-attack as an opportunity to settle the marked group. ]
;B[bg];W[dh];B[dg];W[cg];B[ff]TR[ck]
C[With an early ko, it is often the case that there is no effective ko threat. In this case, Black allows White to win the ko, and in return will connect up to the side with 35. B29 (marked) induced the ko, but also has the extra value of threatening to live on the side, so it will not necessarily become a wasted move. ]
;W[ch];B[df]TR[ck]
C[Black is safely connected with 37. The marked stone still gives Black potential to live on the side. Does White save the corner or not (see var)?]
(;W[bf]
C[White sacrifices the corner, probably the correct choice. ];B[be];W[ag]
;B[ce];W[em]
C[W42 encloses Black while reducing Black's eye space. There is a bit of aji, but locally the left side is White's territory now. White's side is more than 20 points larger than Black's corner, but Black has sente and two corners on the right. This is about even. ]
;B[nc];W[oq];B[lp]
C[Now White should continue in the lower right (see var). ]
(;W[md]
C[White 46 was premature, as the lower left was more important. ];B[np];W[op]
;B[fn]TR[eg]
C[Starting with Black 49, there will be a lot of dancing around right and left, and strange as it might seem, there is a good reason for this. A big ko fight seems likely in the lower right, and White has one valid ko threat that is marked. Black needs a ko threat, and B49 is forcing now, but not big enough to be a valid ko threat later. Black needs to create a big ko threat on the left before starting the ko. ]
;W[gn];B[oo]LB[fn:A][gn:B][op:C][oo:D]
C[The timing of the A-B exchange is important. Black took a small loss with this exchange, so it is not a move to be played at any time. In the context of an upcoming ko, there is a need for Black to create a ko threat. With the C-D exchange White is already heading towards the ko, and backing down from that will cause a loss for White, balancing the loss for Black on the left. ]
;W[no]
C[Black is not quite ready to start the ko (see var). ]
(;B[go]LB[fn:A][no:B]
C[Black cuts with 53 to increase the size of a ko threat on the left. Just as with the attachment at A, the timing is important. Black 53 is going to cause a local loss for Black, but that will be balanced by White's cut at B. After cutting at B, White is committed to a ko in the corner, and avoiding the ko variation will cause a sizable loss for White. ]
;W[gp];B[po]
C[Now Black is ready to play the ko (see var). ]
(;W[ho]
C[White avoids the ko to make a trade. ];B[nn]LB[fn:A][go:B][op:C][no:D]
C[While White has magnificent thickness, it is all in the same place, and I would say White is overconcentrated in the lower left. In this trade on the lower side, Black A and B lost points, but that was in an area where the fighting was already over. White C and D were losses in an area that was unfinished, and now Black will have a huge advantage in fighting on the right plus a big potential territory in the LR corner. ]
;W[mc];B[nd]LB[mc:A]
C[After covering at A , one might expect White to continue on the upper side (see var). ]
(;W[qi]
C[White invades at 60 while there is still some room to make a base, leaving the group in the upper side to fend for itself. ]
;B[kc];W[kd];B[me]
C[The hane at the head of 2 stones is a vital point (see var). ]
(;W[nb]LB[ob:A][jc:B]
C[If Black covers at A, then White can play at B. ];B[le];W[oc];B[od];W[lb]
LB[jc:A][pc:B]
C[W68 was good shape, making miai of A and B. ];B[ld];W[pc];B[qc];W[qb];B[lc]
;W[mb];B[rb]
C[White can cut once to get sente (see var). ]
(;W[pb]
C[The upper side fight was a local victory for White, living easily in an area dominated by Black. After the trade on the lower side, Black's play in this game is reminiscent of the Master series, in which AlphaGo often had a distinct lead and could afford to play solidly. AG attacks to control the flow of the game, and now we shall see Black use an attack on the right to make a large territory in the lower right. ]
;B[qk];W[pk];B[ql];W[qd]
C[White grabs some extra territory in the corner before dealing with the right side. ]
;B[qe];W[rc];B[rd];W[oi];B[pj];W[qc];B[pf];W[oj];B[pi];W[ph];B[qj];W[of]
TR[nd:pd]
C[White 92 is at a vital point, the center of the marked three stones. ]
;B[og];W[ng]TR[qd]
C[ I would say that White 94 was already part of White's plan when it cut at the marked point. The cut caused this weakness in Black's shape. Black cannot cut on the 5th line (see var).]
(;B[nf];W[oh];B[mj]
C[Black 97 starts an orderly sequence with which Black dominates the center and finally makes territory of the LR corner. ]
;W[rf];B[re];W[pg];B[mh];W[mg];B[bj];W[dk];B[dl];W[el]LB[bj:A][dl:B][ei:C]
C[While I sometimes accuse AlphaGo of playing meaningless forcing moves, that is not the case with Black A and B. Later Black will play at C to make use of some aji that it has created here. ]
;B[kg];W[qf];B[pe];W[sf]
C[White threatens to connect underneath (see var). ]
(;B[sc]TR[kb]
C[Black 11 reduces White's corner territory by almost 9 pts, with the added value of the marked forcing move, so this is a big move. ]
;W[ri];B[kb];W[la];B[lr]
C[Black 115 is a huge move that secures the corner territory and starts the endgame.]
;W[nl];B[ei];W[gi];B[gh];W[ii];B[bm]
C[Black cannot live on the side, but will get to play a forcing move from outside. ]
;W[dm]
C[With White 122, Black does not have room to live (see var). ]
(;B[cj];W[eg];B[fh];W[ae];B[bd]TR[cj]
C[With the marked stone, Black is threatening to live on the side (see var). ]
(;W[ai]
C[White 128 kills Black while making a potential eye for White on the side. ]
;B[bo];W[bl];B[cl];W[cm];B[bp];W[bq]
C[White can squeeze to kill the Black group (see var). ]
(;B[ak]TR[di]
C[Avoiding the squeeze, Black 135 sets up to force with the marked cut. ]
;W[ap];B[al];W[an];B[bn];W[ao];B[di];W[ad];B[ac];W[af];B[bc];W[bi];B[fj]
C[This forcing move at 147 made the whole battle on the left worthwhile for Black. ]
;W[ek];B[rh];W[rj];B[rk]TR[rh]
C[The marked stone is asking White to make a choice. White can live, but at a small cost in territory (see var). ]
(;W[qh]TR[rg]
C[White stubbornly refuses to give up any territory with 152, but now Black can kill locally with a play on the marked point. ]
;B[ml]TR[nk]
C[It was slightly better for Black to play at the marked point, denying White an eye in the center. ]
;W[nk];B[mk];W[pl];B[qm];W[mo];B[lo];W[mn];B[mm];W[qq];B[rq];W[rp];B[ro]
;W[nm]TR[ok]
C[White 166 plays a part in securing a potential eye for White at the marked point, thus giving life to the right side group. ]
;B[ln];W[on];B[mp];W[pn]
C[White 170 is a clever move that is setting up forcing moves from the corner (see var). ]
(;B[qo]
C[White gained a few points by pushing Black around in the LR corner. Next, the center and the lower side are miai. ]
;W[rr];B[sp];W[gj];B[iq]
C[Black is still more than 10 points ahead before komi. 
];W[pr];B[nr];W[nn]
;B[il];W[hh];B[hg];W[ig];B[gr];W[jo];B[in];W[jq];B[ip];W[io];B[jp];W[jm]
;B[jk];W[kf]
C[White 192 reduces Black's territory while starting to cut Black off in the center. ]
;B[jh];W[ih];B[ji];W[ij];B[jj];W[km];B[jc]TR[ka]
C[Black 199 forestalls White's endgame play at the marked point. ];W[lg]
;B[jg];W[if];B[lh];W[id];B[ic];W[ka];B[ja];W[ia];B[jb];W[kk];B[jf];W[lm]
;B[je];W[mi];B[li];W[ni];B[fr];W[er];B[jl]
C[Starting now, White begins to throw away points, and maybe that's AlphaGo's way of preparing to resign (see var). ]
(;W[sb];B[sa];W[hl];B[im];W[sd];B[se];W[sr];B[pp];W[ko];B[kp];W[lk];B[lj]
;W[fs];B[sg];W[sq];B[rp];W[qn];B[rn];W[rm];B[sm];W[sk]
C[White 240 saves the White group (see var). ]
(;B[rl];W[sh];B[si];W[sj];B[sl];W[sh];B[hr];W[nq];B[pq];W[or];B[mr];W[he]
;B[ge];W[gm]
C[I have added a final diagram to show how I expect thegame to continue. ]
(;B[si]
C[B wins by 5.75 stones (10.5 points).])
(;B[ik];W[hk];B[si];W[qg];B[pm];W[rg];B[oa];W[na];B[qa];W[ob];B[ie];W[lf]
;B[ke]
C[This variation shows how the two White groups end up living. Black has an abundance of ko threats, and will easily win the ko in the UR corner. Black wins by 5.75 stones (10.5 pts)]
))
(;B[sl];W[pm];B[sj];W[qg]
C[White is alive. ]))
(;W[he];B[ge];W[lk];B[lj];W[qn];B[rn];W[sk];B[sl];W[sj];B[sm]TR[sr]
C[White has a forcing move at the marked point, so Black must answer at 10. ]
;W[hl];B[im];W[ko];B[kp];W[hm];B[oa];W[na];B[qa];W[ob];B[ie]
C[White 15 is the final large move. ];W[lf];B[ke];W[hr];B[hq];W[gq];B[ir]
;W[fs];B[hs];W[pm];B[ik]
C[After 29, only 1 and 2 point moves are left. ];W[hk];B[sb];W[ra];B[sa]
;W[kj];B[ki];W[fi];B[gg];W[ej];B[hf];W[jn];B[sd]
C[Black wins by 2.75 stones (4.5 points with Japanese rules)]))
(;B[nn];W[pp]
C[With the atari at 2, White has created trouble inside the corner (two vars for Black's move). ]
(;B[qo];W[rr];B[sp];W[pr]
C[White is alive. ])
(;B[sp];W[qn];B[rn];W[qo]
C[A huge ko in the corner. ])))
(;W[rg];B[sj];W[qh];B[iq]
C[White can live with 1, and the price is small, just a forcing hane at 2. Black takes the final large point at 4, and is winning by well more than 10 points before komi. ]
))
(;B[al];W[ak];B[bk];W[aj]))
(;W[di];B[bo];W[bp];B[ao];W[cm];B[al]TR[cj]
C[Black lives on the side. Note that the marked stone is making the difference. ]
))
(;B[bo];W[cm];B[cl];W[bp]
C[Black is dead. ]))
(;B[ri];W[sd]LB[ne:A]
C[With the weakness at A, Black cannot cut White off. ]))
(;B[oh];W[pg];B[nh];W[mh]
C[Black cannot cut at 1, as White can capture in a ladder. ]))
(;W[qd];B[rc];W[pb];B[qe];W[ql];B[kb];W[la];B[rm];W[rl];B[lr]
C[Cutting once at 1 before living with 3 is a sacrifice play, forcing Black 4 and giving White sente to take the important point at 5. It is very clever, but there is a negative aspect for White too. When Black plays at 4, Black's local gain is significantly more than if White had not cut at 1. In this case, there is also the added value of a forcing move at 6, and the fact that Black 10 is the final big point. Maybe because Black was ahead already, this will not be good enough for White. ]
))
(;W[jc];B[mb];W[lc];B[kb]TR[me]
C[If White covers at 1, Black can connect underneath with 2. The marked stone is at a vital point to destroy White's shape. ]
))
(;W[me];B[pg];W[qi];B[qk];W[oi];B[mg]
C[White extending at 1 might seem to be the natural move, but after Black 2, White must do something about the right side moyo. Black's thickness will help to attack, and after Black 6 both White groups are under attack. ]
))
(;W[mp];B[mo];W[nq];B[nn];W[lo];B[np];W[eg];B[ef];W[no];B[gm];W[mn];B[hn]
C[The trade to 12 slightly favors Black. ]))
(;B[po];W[mp];B[mo];W[nq];B[nn];W[lo];B[np];W[eg]
C[It is said that there is no ko threat for the early ko. White cuts at 6 to start a ko, and this would usually be unreasonable, but it works when White has ready the huge ko threat at 8. White threatens to gain almost 50 points in the corner while weakening Black's upper side group. ]
;B[ef];W[no];B[mn];W[kp];B[lq];W[kq]
C[When Black runs out of ko threats and connects at 11, White has an advantage in the local fight with 12 and 14. ]
))
(;W[on];B[pq];W[np];B[qn];W[jq]
C[White should jump out at 1, the most natural looking move. Black 2 and 4 are the most popular modern joseki. After 5, White has potential to attack on the lower side and this attack is more immediately important than invading the upper side Black moyo. ]
))
(;W[be];B[bf];W[db];B[fn];W[gn];B[gm]
C[If White lives with 1 and 3, Black can break out into the center with 4 and 6. White's group on the left side is not yet completely alive, and this looks good for Black. ]
))
(;W[dk];B[bi];W[cl];B[bj];W[bl];B[be]
C[Locally, White 1 is a common shape for White, but it is not good in this case. Black will connect underneath and attack with 6. Black's group on the side is alive now, and that makes the attack against White's corner very powerful. ]
))
(;W[eg];B[dh];W[fj]
C[If I were White, I would press at 1 and jump at 3, attempting to save White's corner group while continuing to attack on the side. ]
))
(;W[dg];B[dh];W[fj];B[fh];W[df]
C[If White peeps at 1 and then covers at 5, White's UL corner group is connected and alive. ]
))
(;W[eh];B[di];W[ei];B[cj];W[ck];B[dk];W[ej];B[cl];W[bk];B[dl]
C[If White plays from above with 1, Black can take the side territory with 2~10. This is good for Black. ]
))
(;W[cg];B[eq];W[er];B[fr];W[ep];B[fq];W[dp];B[go];W[dr];B[jq]
C[If White plays away at 1, Black can play strongly with 2 and 4. Go Seigen actually suggested exactly the same sequence, and I see this as some extra evidence that Go Seigen was indeed the remarkable player that we know him to have been.  ]
))

