(;GM[1]FF[4]SZ[19]AP[SmartGo:3.1.2]CA[utf-8]
GN[Game_006]
PW[AlphaGo Master]
PB[AlphaGo Zero]
KM[7.5]
RE[B+Resign]
RU[Chinese]ST[2]
TM[7200.0]OT[3x60 byo-yomi]MU[1]MU[0]
C[Commentary by Michael Redmond 9P

AG Zero is back, this time "with a big group that looks like it's about to die, just floating around in the middle of Master's moyo" says Michael Redmond 9P in his commentary https://youtu.be/F0Kw7sziZGQ. "But Zero doesn't seem to be worried, because it plays away and does all sorts of stuff." 

To support this content, please consider joining or renewing your membership in the American Go Association; click here http://www.usgo.org/join-now for details.

Video produced by Michael Wanek and Andrew Jackson. The sgf files were created by Redmond, with editing and transcription by Garlock and Myron Souris.]
;B[pp];W[dp];B[pd];W[dd];B[fq];W[cn];B[cc];W[cd];B[dc];W[ec];B[eb];W[fc]
;B[fb];W[gc];B[nq];W[qf];B[gb];W[hc];B[qi]LB[pi:A][qj:B][qh:C][pj:D]
C[This is the only game of the 20 game set in which Zero played the pincer at 19. In other games it played at A or B. This is a board position in which a human pro would also want to pincer, and I would not be sure which pincer is the best. The pincers at C or D also look like possible choices. ]
;W[qn]LB[nq:A][nd:B][qi:C]
C[When Black already has the stone at A, White 20 looks like a heavy move that might lead to a difficult fight for White. In most of the games, Master played the double kakari at B. The position of Black's pincer stone at C is unique to this game, but I don't see an explanation for White 20 in that, as the position of Black's stone at C works well for Black in this game. ]
;B[qo];W[pn];B[ql]TR[pn]
C[White's marked stones are heavy and without a base. ];W[pj]LB[qf:A][qc:B]
C[White tries to force from above. This is an example of Master using the shoulder hit in an attempt to control the center and settle it's weak group. Depending on how this works, the stone at A can be sacrificed, as White can reduce the loss with an invasion at B. ]
(;B[pf]TR[pj]
C[I think this is a very important point in the game, where Zero takes control by playing a move that was probably not predicted by Master. Black 25 might seem to be playing away, but actually this is a powerful response to White's marked shoulder hit. It will turn out that Black 25 is much better than answering underneath (see var). ]
(;W[pl]LB[pf:A]
C[Both players seem to be ignoring the other, but there is some logic to each move. Answering Black A directly is not good for White (see var). ]
;B[qe]LB[pf:A][qj:B]
C[Starting with the attachment at A, Black has created a highly efficient shape with 27. Establishing this strong shape in the upper right was much more valuable than simply connecting at B would have been. In this short exchange on the right side, Zero has shown superior positional judgement as well as reading ability. ]
;W[eq];B[fp];W[jp];B[ee]LB[cc:A][ed:B]
C[Zero likes to play the peep at 31 after the invasion at A. If White answers at B, this will be a good exchange for Black. ]
;W[dg]LB[df:A][ed:B]
C[When White plays on the left with 32 or at A, Black will be looking for a way to make the cut at B effective later. It is hard to say if this exchange in the upper right was good for Black, as it depends on how the game proceeds from here on. ]
;B[fm];W[dm]
C[White 34 is a good shape move that mostly removes the threat of a Black invasion at A, and puts some pressure on the outside Black group. ]
LB[cq:A];B[fk];W[hp]LB[dm:A][fn:B]
C[In combination with White's stone at A, White 36 threatens to sever Black's connection with a play at B, while taking away Black's base on the lower side. ]
;B[lq]TR[fp:fq]
C[Black 37 is a big play that strengthens Black's LR corner while reducing the value of the two marked stones. As the game progresses, we will see Black gradually setting up an attack on White's group on the right, and 37 is the first step in that direction. ]
;W[hm]LB[dm:A][hp:B]
C[Working with the stones at A and B, White 38 is a vital point that reduces Black's eyespace, and puts a lot of pressure on Black's group in the center. ]
;B[hj];W[pi];B[qg];W[bd];B[bc];W[ff]TR[ee]
C[White 44 captures the marked Black stone, and is a thick move. ];B[fr]
LB[iq:A][do:B][cq:C]TR[fp:fq]
C[Black 45 brings the marked two stones back to life, with the peep at A, and forcing moves such as B linked with the potential invasion at C. ]
;W[hk];B[dh]LB[fp:A][fm:B][ij:C][fn:D]
C[The tricky timing of Black 47 make this a very volatile position. Black's 3 stones at A can make a living shape on the side, but are not really connected with the stone at B yet. At this moment in the game, Black is prepared to sacrifice any part of this Black group on the left, depending on how White tries to attack. While White has potential attacking moves at C or D, when Black attaches at 47, the left side is important too. ]
;W[eh];B[di];W[cg]
(;B[ik]TR[hk]
C[Black 51 is the strongest answer to White's marked attachment. Zero is trying to make a super-efficient shape, where the safer way to play would be less effective (see var). ]
;W[hl]LB[ij:A][gj:B]
C[White 52 is a solid move that makes miai of A and B. ];B[ei]TR[ik][hl]
C[The marked exchange is great for Black as far as shape is concerned, but there is no way for Black to connect everything up. With 53 Black starts to make shape on the left side. ]
(;W[gj]
C[If White answers on the left with this move, Black will be able to connect up to the center as in the variation. ]
;B[fh]
(;W[hi]TR[eh]
C[It is correct for White to sacrifice the marked stone (see var). ];B[ij]
;W[gi];B[eg];W[ef];B[gn]
C[With 61 Black finally connects to the lower side. ]
(;W[lp]
C[With 62 White is attempting to prevent Black from living on the lower side( see var). ]
;B[io]LB[jm:A][gk:B]
C[With  Black is threatening to play at A next, threatening the cut at B. ]
;W[dk];B[ek];W[jm]
C[White  maintains White's strong position in the center while attacking Black. ]
;B[mp];W[lo];B[gg];W[jh]
C[While I would be uneasy playing such a dangerous game with Black, Zero seems to be comfortable with this type of a game, and this is becoming a demonstration of the Go proverb 'Big dragons never die', as Black has potential eyespace in the LL corner, the lower and left sides, and some potential in the center for the marked false eye to become a real one. ]
TR[eh];B[mo];W[kq];B[ol];W[pk];B[ln];W[jo];B[om]
C[Black takes the offensive with 77 on the right side. Black's big group still has potential eyes in various places, and it is difficult for White to attack successfully. ]
;W[ll];B[df]
C[Black 79 is a troublesome cut for White to deal with. Black is looking to squeeze from the center, with a Black stone at A making a difference in Black's eyeshape, and some potential to escape to the right. Black is also looking at a potential squeeze on the left side. ]
LB[fg:A];W[fe];B[nj];W[hr]
C[With 82, White finally takes away Black's eyespace on the lower side. ]
;B[ge]
(;W[cf]
C[White 84 removes the potential squeeze on the left (see var). ];B[jf];W[li]
;B[dr];W[er];B[es];W[cq];B[cr];W[bq];B[ck];W[em];B[el];W[dl]
(;B[eo]
C[Black 97 secures Black's connection here while setting up a life in the corner (see var). ]
;W[cj]
(;B[mi]TR[eo]
C[Black plays away with 99, continuing to attack on the right. In addition to connecting the Black group, Black's marked stone will help Black to make a living shape in the corner (see var). ]
;W[lh];B[rj]
C[After Black 101, it already looks difficult for White on the right side. ]
;W[op];B[oq];W[qq];B[qp];W[nn];B[on];W[oo];B[mm];W[en]
(;B[fn]
C[With Black 111, there is another way to connect that looks feasible (see var). ]
;W[nk];B[mk];W[ml];B[ok];W[gf]LB[hg:A][if:B]
C[White 116 cuts Black off in the center, If Black A, White can cut with B. ]
;B[dq]
C[Black 117 makes life for the Black group. ];W[ep];B[cp];W[do];B[bp]LB[fn:A][go:B]
C[Finally we can see a ko setting up. In this game sequence, Black's move at A has become bad, in that the Black group would have been connected if that stone had been played at B. However, Zero seems to have already calculated that this is the safest course for Black, as Black can afford to sacrifice the left side in a ko. ]
;W[fo];B[go];W[gp];B[eo];W[pq]
C[White has several valid ko threats on the right side, with that dead White group, so White is going to win the ko. ]
;B[rn];W[fo];B[dj];W[bk];B[eo];W[rm];B[ro];W[fo];B[hf];W[hg];B[eo];W[po]
;B[rq];W[fo];B[nl];W[lk];B[eo];W[rr];B[sr];W[fo];B[hh];W[ig];B[eo];W[pr]
;B[or];W[fo];B[ii]
(;W[gk]
C[White must be careful to connect at 154, as Black's ko threat was actually threatening to make eyes. ]
;B[eo];W[br];B[bs];W[fo];B[fd];W[de];B[eo];W[ds];B[cs];W[fo];B[km]
(;W[ih]
C[White 166 is an important point that gives White good aji (see var). If White had played this move at A, Black would have had more ko threats in the center, so it seems reasonable for White to reduce Black's ko threats with this move. ]
LB[jl:A];B[eo];W[mn];B[no];W[fo];B[ci];W[cl];B[eo];W[ar];B[ap];W[fo];B[fg]
;W[ed];B[eo];W[gs];B[fs];W[fo];B[in];W[jn];B[eo];W[sp];B[ps];W[fo];B[mg]
;W[eo];B[lc]
C[White wins the ko to capture the left side, and Black plays the big point at 191. Black has a lead in territory. ]
;W[lf];B[kl];W[oc];B[mc]
C[Black 195 might be strange looking, but in this case it is an effective move. White does not have room to live. ]
;W[qh];B[rh];W[qr];B[rs];W[mf];B[od];W[ng];B[oh];W[kc];B[kb];W[jc];B[ld]
;W[kd];B[ad];W[ae];B[ac];W[pb]
C[This is where Master starts to play some bad moves, but White is behind by a small margin in any case. ]
;B[nb];W[jk];B[kj];W[lm];B[kn];W[kk];B[lj];W[jl];B[nm];W[nd];B[nc];W[qc]
;B[rd];W[oe];B[be];W[nh];B[ag];W[bh];B[og];W[ne];B[ja];W[pe];B[qd];W[rf]
;B[rg];W[ri];B[si];W[pg];B[ph];W[of];B[pg];W[rc];B[ob];W[db];B[cb];W[jb]
;B[ha];W[hb];B[ia];W[pc];B[sf];W[lb];B[ka];W[ib];B[la];W[ca];B[da];W[pa]
;B[ra];W[rb];B[qa];W[rp];B[qs];W[ea];B[db];W[mh];B[mj];W[ga];B[mb];W[ma]
;B[fa];W[bf];B[aq];W[lr];B[af];W[jj];B[ah];W[bi];B[ki];W[ji];B[mq];W[sd]
;B[re];W[ce];B[ae];W[sc];B[sa];W[bo];B[mr];W[ks];B[as];W[kh];B[bn];W[bm]
;B[an];W[co];B[ao];W[ni];B[oi];W[oj];B[nk];W[mn];B[nn];W[ko];B[mn];W[le]
;B[gr];W[hs];B[ds];W[hq];B[ai];W[aj];B[am];W[al];B[md]
C[B+2.75 (5.5)])
(;W[eo];B[ih];W[jg];B[jl];W[im];B[kl];W[gh];B[fg];W[ed];B[lc]LB[eo:A][lc:B][jg:C]
C[If White fills the ko at A, Black can save some stones in the center with sente before playing a final big move at B. White's group at C is in danger of being cut off, which limits how strongly White can fight on the upper side. ]
))
(;W[ih];B[gk];W[gh];B[fg];W[fd];B[fj]
C[If White cuts at A, Black can make use of White's damezumari to live with this sequence. ]
LB[ih:A]))
(;B[go]
C[When Black plays at A, this is better for Black when Black gets to live in the corner, but there is a drawback when White takes away Black's eyes (see 2 vars). ]
LB[go:A]
(;W[gf];B[dq];W[ep];B[cp];W[do];B[bp]TR[go]LB[gf:A][dq:B]
C[If White pushes through at A, Black can live with the sequence from B. The marked stone gives Black a safe connection. ]
)
(;W[ep];B[gf];W[gk];B[fn];W[ie];B[if];W[nh]LB[ep:A][gk:B]
C[If White plays at A to take away Black's eyes, Black will try to escape into the center. White can use the forcing move at B to reinforce White's group in the center. It is not clear to me how this will turn out, but this looks dangerous for Black. ]
)))
(;B[dq];W[ep];B[cp];W[do];B[bp]
C[Black is alive. ]))
(;B[rj];W[fn];B[en];W[fo];B[go];W[eo];B[ep];W[do];B[dq];W[hf]LB[rj:A][fn:B][hf:C]
C[If Black plays away at A, White can cut at B. Black lives in the corner, after which Black's group on the left side is in danger when White plays at C after the forcing sequence in the LL corner. ]
))
(;W[ie];B[ck];W[dl];B[cf];W[bg];B[bf];W[af];B[ae];W[ag];B[bh];W[be];B[ch]
;W[ad];B[ah];W[ae];B[bl];W[dj];B[fi];W[cj];B[bj]LB[ie:A][cf:B][fg:C]
C[If White surrounds Black with A, Black can squeeze from B on the left side to make a living shape. Black has a forcing move at C that can be used to secure an eye in the center. ]
))
(;W[hn];B[do];W[co];B[iq]
C[If White covers at A, Black will be able to live on the side after B. ]
LB[hn:A][iq:B]))
(;W[eg];B[gk];W[gi];B[ij];W[gh];B[gn];W[hn];B[do];W[co];B[iq]LB[eg:A][ij:B][iq:C]
C[If White connects at A, Black can force from the center with B and live on the side with C. Much will depend on how the fight continues in the center, but at this point Black has a lead in territory. ]
))
(;W[fh];B[fi];W[ij];B[hi]LB[ik:A]
C[Black has good shape, with the cutting stone at A causing White to have bad aji. ]
))
(;B[gk];W[ik];B[ei];W[fh];B[fi];W[ji];B[hh];W[er]LB[gk:A]
C[If Black starts by bumping against at A, it will be relatively easy for Black to connect it's stones. However, in this final shape, Black is connected without the stone at A, and this stone has become slightly redundant, giving White an extra move in the corner. While this seems to be a reasonable way for Black to settle the weak group, it was not good enough for Zero. ]
))
(;W[pg];B[qg];W[pe];B[of];W[qd];B[oe];W[qe];B[qc];W[pc];B[od];W[qb];B[rc]
;W[rb];B[rd];W[rg];B[qh];W[re];B[se];W[rf];B[oc];W[pb];B[rh];W[sc];B[ol]
LB[pg:A][qg:B][ol:C][pj:D]
C[If White plays at A, Black will cut at B, and the following sequence is mostly forced. Finally, Black jumps out at C, and White's shoulder hit at D has lost it's original meaning. This is good for Black. ]
))
(;B[qj];W[pl];B[pk];W[ok];B[qk];W[nl]LB[qf:A][qc:B]
C[This is what Master wanted to happen. The stone at A is not dead yet, and White can always trade to the corner with B. White has potential to control the center, and that could work well with White's moyo on the left. ]
))

