(;GM[1]FF[4]SZ[19]AP[SmartGo:3.1.2]CA[shift_jis]
GN[19]
PW[AlphaGo]
PB[AlphaGo]
EV[AlphaGo selfplay]RO[19]
KM[7.5]
RE[W+R]
RU[Chinese]MU[1]
C[AlphaGo vs. Alphago with Michael Redmond 9p: Game 19

As usual in these AG-AG games, you'll be wondering which group is going to die, but, also as usual, they all come back to life, and the game is pretty close. ]
;B[pd];W[dd];B[pp];W[cp];B[eq];W[dn];B[cc]
C[This is a position where the human move for Black would be an extension at A, a kakari at B or C, or even Sanrensei at D. ]
LB[iq:A][fc:B][cf:C][pj:D]
(;W[dc]
C[Speaking from what we thought to be normal before AlphaGo, White has potential on the left side, so should be covering from the left (see var). With changes in the popular joseki patterns that came after AG, covering on the 'wrong' side as in this game is now being played by human pros.  ]
;B[cd];W[cf];B[ce];W[de];B[bf];W[nq];B[qn]
C[In theis self-played series, AG played this opening in 3 games with a different choice for White's next move in each game. ]
(;W[nc]
C[In this set of games, AG played 3 identical openings that diverged at this move (see 2 vars). ]
;B[cg]LB[qf:A][pf:B]
C[While it would have been normal for Black to play at A or B, Black 17 is also a big point. ]
;W[df];B[cb]LB[cg:A][cb:B]
C[The sequence from Black A to B punishes White for playing away when the joseki was not finished. This gives Black good shape, and sets up a potential attack against White's wall with a pincer on the upper side. ]
;W[qf]
C[White's double-kakari is a highly valuable move that gives White a local advantage in the upper right. Both sides are punishing each other for playing away, and the overall position is about even. ]
;B[pf];W[pg];B[of]
(;W[qe]
C[In recent years, it has become popular for White to attach at A with this move. There is a ladder variation to that joseki (see var). ]
LB[qd:A];B[qd];W[md];B[oc]
(;W[qj]
C[Extending on the right side, White diverges from the standard joseki (see var). ]
(;B[jc]
C[The basic joseki indicates that there is a big move in the UR corner (see var), but in this board position this pincer on the upper side is more important. ]
;W[ob]
(;B[nd]
C[Black 31 is an important move that maintains Black's connection with the marked stones (see var). ]
TR[of:pf]
(;W[pc]
C[The eyespace of both Black's corner group and White's group on the upper side is important. White tries to take away the corner with the atari at 32. The joseki move for Whitewas at A, but in this position, that would have been too weak (see var). ]
LB[nb:A];B[od];W[mb];B[lc];W[mc];B[re];W[rf];B[pb]
(;W[mf]
C[If White extends at A, the corner will become a ko (see var), and with White I would have wanted to exploit that immediately. ]
LB[qc:A];B[pi]
C[Adding a stone at A would be a painful choice for Black, so Black moves out instead. ]
LB[qc:A];W[qi];B[ph];W[je];B[gd];W[he];B[fc]
(;W[pq]
C[White has some aji at A, but it is not very effective yet (see var). White's attachment at B is a move that AG likes, while the normal looking move for White on the lower side would be the pincer at C. ]
LB[ic:A][pq:B][iq:C];B[qq];W[qr];B[oq];W[pr];B[op];W[or];B[rq];W[np];B[ff]
;W[dh];B[ch];W[dg];B[en];W[em];B[lq]LB[en:B][lq:C][ff:A]
C[After starting an attack with A, the order of Black's moves at B and C is not easy to explain. Black C is actually a very big point, so I would be happy to play there without playing A and B first. ]
;W[nn];B[fh];W[di]
(;B[dk]
C[Black continues to chase White in the upper left with 67, and this move will combine with the previously played attachment at A to create a suprising trade. If I were Black, I would probably be focused on building on the lower side, so in the variation I will show how I would play with Black. ]
LB[en:A];W[fi];B[dm];W[fm]
C[White A helps defend White's group in the upper left by playing strongly towards the center, and offers the corner to Black as a trade. ]
LB[fm:A];B[do];W[cn];B[co];W[bn]
(;B[dp]TR[en]LB[bo:A]
C[Instead of pushing through at A (see var), Black pulls back with 75 to save the marked cutting stone. ]
;W[fn];B[eo];W[bo];B[cq];W[dl]LB[md:A][np:B][pd:C][qn:D][lq:E]
C[At this point in the game there are still a number of groups that are not fully alive. White A and B are groups that are not exactly weak, but do not have a living shape yet. Black C and D are not completely alive. The status of Black E and the lower side is not decided yet. ]
;B[ql]LB[ql:A][np:B][rd:C]
C[Black A might look small, but it is actually an important point. This move settles Black's group in the lower right corner, and takes a step towards attacking the White group at B. If Black plays at C next, the White group on the right will not be fully alive, so by weakening this White group, Black is indirectly strengthening the Black group in the upper right corner. ]
;W[ic]LB[he:A][ic:B][qj:C][nn:D]
C[After playing at A almost 40 moves ago, White always had somepotential to play the tsuke at B. My interpertation of the timing of this move would be that by adding a stone to strengthen White's group on the upper side, White is lessening the danger of Black attacking White's other groups at C and D. ]
;B[id];W[jd];B[mr];W[nr]
(;B[hd]
C[When Black simply connects like this, Black is going to lose the semeai. The tesuji was to play an atari from underneath first (see var). ]
(;W[rl];B[rm];W[pl]LB[qj:A][nn:B]
C[With this attachment, White reinforces the groups at A and B. ];B[gi]LB[gi:A][ip:B][lq:C]
C[Black's hane at A is a shape that is usually sente, but it was not forcing in this position, and I suggest that it was a slack move. Black should have played at B to make a position on the lower side while protecting the weak stones at C, and Black has a small lead. ]
;W[qk];B[qm];W[jq]LB[jq:A]
C[White A is a big move that takes away Black's potential for territory on the lower side while creating a weak Black group. This is where I think White has recovered from a disadvantage earlier in the game. ]
;B[lo];W[jo];B[kc]LB[lm:A]
C[Black switches to the upper side, which is admittedly huge, but the timing is unexpected. Black is in immediate danger on the lower side, so the natural move would be to jump out at A. ]
;W[ib];B[jb]
(;W[gr]TR[lo][lq][mr]
C[While I was suprised by Black not running out into the center, White also suprises me by not going after the marked Black group (see var). That said, White's slide to the second line is a big move that sets up an attack on Black's group in the LL corner, and this still looks good for White. ]
;B[lm];W[bp]
(;B[gp]
C[The variation shows the simple way for Black to live in the corner. ];W[dr]
;B[gq]
(;W[dq]
C[Cutting here when Black can capture the two White stones is strangely effective when Black takes the gift. The variation shows the normal move for White. ]
;B[cr];W[fo];B[ep];W[hr];B[er];W[br];B[hn];W[ip]
C[White threatens to kill Black's group on the left, while alsio looking at cutting at A. ]
LB[lp:A];B[mo]
(;W[no]LB[fp:A]
C[White could have captured by pushing through at A, but saving White's group on the right was more important (see var). ]
;B[ho];W[jm];B[hl];W[jk];B[ml];W[im];B[hm];W[gj];B[fj];W[gk];B[ik];W[jj]
;B[hi];W[ei];B[el];W[cl];B[gl]TR[gj:gk]
C[Black makes a connection to the center by putting the marked White stones in damezumari. ]
;W[fl];B[ok]
C[This move attacks White's group at A while escaping with Black's group on the lower side. ]
LB[nn:A];W[kr];B[jh];W[mj];B[mk];W[lr];B[mq];W[ms];B[lh];W[lj];B[pk];W[qg]
;B[nh];W[ka];B[ja];W[lb];B[oa];W[na];B[nb];W[ld];B[hb];W[ob];B[jl];W[kl]
;B[nb];W[il];B[hk];W[ob];B[jn];W[in];B[nb];W[fk];B[ii];W[ob];B[ls];W[ns]
;B[nb];W[ij];B[hj];W[ob];B[kn];W[io];B[nb];W[kd];B[hc];W[ob];B[rd];W[rk]
;B[nb];W[kg];B[kh];W[ob]
(;B[sh]
C[The way that Black played ko threats here was not correct, as shown in the variation. ]
;W[sg];B[nb];W[kb];B[ia];W[ob];B[rh];W[qh];B[nb];W[og];B[ng];W[ob];B[sf]
;W[se];B[nb];W[mg];B[mh];W[ob];B[sl];W[ri];B[nb];W[ma]
(;B[bj]
C[Black cannot kill the White group (see var). ];W[bi];B[ci];W[cj];B[bh]
;W[bk];B[ai];W[jg];B[om];W[bq];B[ds];W[db];B[lk];W[kk];B[ck];W[dj];B[bl]
;W[ek];B[ak];W[rr];B[qp];W[ob];B[pa];W[ca];B[ba];W[da];B[bb];W[on];B[pn]
;W[nj];B[nk];W[nf]
(;B[sd]
C[Covering on the st line was not correct (see var). ];W[hg];B[ck];W[gg]
;B[fr];W[fb];B[gb];W[qb]
C[White is winning by a small margin. ])
(;B[rb];W[ck];B[if];W[ie];B[ig];W[fb];B[gb];W[gg];B[fg];W[gf]
C[It is correct for Black to protect at A. White will win by about 2.5 points in this variation. ]
))
(;B[kf];W[ob];B[pa];W[jf];B[lg];W[lf];B[jg];W[nf];B[ne];W[me];B[ke];W[pe]
;B[oe];W[qc];B[rc];W[qb];B[nb];W[rb]
C[If Black tries to kill White, Black's corner group will run out of liberties. This is a ko, but it will end badly for Black. ]
))
(;B[rh];W[qh];B[nb];W[kb];B[ia];W[ob];B[sf];W[sg];B[nb];W[og];B[ng];W[ob]
;B[se];W[ri];B[nb];W[mg];B[mh];W[ob];B[sh];W[rg];B[nb];W[ma];B[bj]
C[The sequence shown starting Black playing a ko threat at A gives Black the same number of ko threats as in the game, and is 4 points better for Black. Even in this variation White has a small lead. ]
LB[rh:A]))
(;W[fp];B[no];W[ci];B[bq];W[aq];B[ds];W[ar];B[ho];W[fq];B[fr];W[fs];B[im]
LB[no:A][dp:B][ho:C][fj:D]
C[In this trade, White might have seemingly gained by capturing a larger group, but this is not true. While capturing White, Black A has the added value of connecting two weak Black groups. With C, Black can save some stones and threaten a semeai. If White protects on the lower side next, Black can continue with D and make some territory in the center. Black will win.]
))
(;W[hr];B[cr];W[er];B[fr];W[fs];B[fq];W[es];B[dq];W[ho];B[bq]LB[hr:A][bq:B]
C[If White pulls back at A, Black can live with the forcing sequence to B. ]
))
(;B[fr];W[gq];B[bq];W[dr];B[er];W[fo];B[cr];W[ci]LB[fr:A][bq:B][ci:C]
C[Black can live by kicking once at A and then covering at B, but this is painful and after White C, Black will have trouble paying komi. ]
))
(;W[qp];B[rp];W[kn];B[hq];W[iq]
C[White's forcing move at A makes it difficult for Black to escape. ]LB[oo:A]
))
(;W[jb];B[kc];W[hb];B[lo]LB[jb:A][lo:B][ie:C][gb:D]
C[I had expected White to continue at A, winning the semeai to get some territory on the upper side. Black will then attack White's group in the lower right with B. Black's group on the upper side is strong, with forcing moves at C and D. The overall position favors Black. ]
))
(;B[ib];W[hc];B[hd];W[jb];B[kc];W[hb];B[kb];W[ia];B[gb];W[ld];B[ka];W[kd]
;B[ja]LB[ib:A][hb:B]
C[If Black plays at A, then the sequence to White B is forced. After that, Black might switch to the lower side, but the local fight will end in a ko as shown. Compared to the game, there is an advantage  for Black in getting a ko instead of losing the semeai outright. The tradeoff is that if Black loses the ko, the marked Black group will become weak. ]
TR[fc][gd:id][ff][fh]))
(;B[bo];W[eo];B[dp];W[fn];B[hq];W[ci]
C[If Black pushes through at A, White can capture a stone in the center. The territory is close, and I like this for White. ]
LB[bo:A]))
(;B[mr];W[nr];B[do];W[co];B[dm];W[cn];B[fn];W[fm];B[gm];W[dl];B[lo]LB[mr:A][do:B]
C[If Black starts with the peep at A and then continues with B and the following sequence, Black can make use of a potential attack against the marked group to build on the lower side. Black is ahead in territory. ]
TR[dg:di]))
(;W[ic];B[id];W[jd];B[ib];W[hc];B[hd];W[jb];B[kc];W[hb];B[ie]LB[ic:A][ie:B][kb:C]
C[White can break into the upper side with the attachment at A, but is not gaining much when Black breaks through at B, preparing to attack White's wall on the left. Black can later play at C to get a ko on the upper side. ]
))
(;W[qc];B[oa];W[nb];B[rc];W[qb];B[qa];W[pa];B[pi];W[qi];B[pb];W[rb];B[sb]
;W[pa];B[qg];W[rg];B[pb];W[bg];B[bh];W[pa]LB[qc:A][bg:B]
C[If White pushes through at A, a ko starts in the corner. White will win the ko, so locally this is a success for White. The ko threat at B is painful though, and while this is not bad for White, the game sequence seems slightly better. ]
))
(;W[nb];B[pb];W[qb];B[qg];W[rg];B[qh];W[rh];B[pa];W[ne];B[od];W[lc];B[gd]
LB[pb:A][qb:B][qg:C][gd:D]
C[If Black can cover at A, the corner will be Black's territory. White B is a tesuji, but Black can counter with the cut at C that prevents White from connecting underneath. Black can attack at D, taking the initiative, and this is good for Black. ]
))
(;B[pb];W[od];B[pc];W[je]LB[pb:A][pe:B][je:C]
C[If Black simply covers at A, White can force with an atari to create the potential cut at B, which makes the difference to give White an advantageous position. White will not play at B immediately, but starts with the capping move at C. ]
))
(;B[nd];W[ne];B[od];W[jd]
C[Locally, Black A is an important move that secures a solid corner territory for Black. However, in this board position it is bad for Black, as White can get an overall advantage by linking up to the wall on the left with the light move at B. ]
LB[nd:A][jd:B]))
(;W[ob];B[nd];W[nb];B[pi]LB[ob:A][pb:B][pi:C]
C[The joseki move was to play a hane at A, and while a joseki dictionary might have Black continuing at B, the pincer at C is a strong attack that is supported by Black's solid position in the LR corner. This is good for Black. ]
))
(;W[qd];B[qg];W[qe];B[ph];W[pc];B[og]LB[qd:A][ph:B][qc:C]
C[If White attaches at A, Black can play this variation if the ladder at B is favorable. Black has a strong position on the right side, and some aji in the corner with a cut at C. I like this for Black. ]
))
(;W[qc];B[pc];W[qd];B[qf];W[qe];B[pe];W[rf];B[cg];W[df];B[cb];W[qg];B[pf]
;W[qb];B[gc]
C[In game 27 White invaded the UR corner at the 3-3 point. This developed into an exciting fight, with 4 separate groups fitting into the space between the marked walls. ]
TR[dc:df][pc:pf])
(;W[cb];B[bb];W[bg];B[db];W[eb];B[cg];W[df];B[bh];W[dg];B[ag];W[qc]
C[In game 36, White continued with the hane at A, making a slightly unusual joseki variation in the upper left. ]
LB[cb:A]))
(;W[cd];B[dc];W[fc];B[fb];W[gc];B[ec];W[ed];B[gb];W[hc]TR[dn]
C[With the marked stone creating a strong position in the lower left, it seems normal for White to play this way to build on the left side. Black will probably invade the left side next, and this is an even result. ]
))

