(;GM[1]FF[4]CA[UTF-8]AP[CGoban:3]ST[2]
RU[Japanese]SZ[19]KM[7.50]
GN[ ]PW[Sorin Gherman]PB[Yifei Gao]WR[7d]BR[6d]DT[2017-08-10]GC[Yifei Gao http://agagd.usgo.org/player/21345/]EV[US Go Congress 2017, Masters]RO[6]PC[San Diego, CA]C[Commentary by Tsuruta Kazushi 4p.]RE[W+Resign]FG[259:]PM[2]
;B[cp]
;W[pd]
;B[dc]
;W[pp]
;B[nq]
;W[qn]
;B[iq]
;W[de]
;B[ce]
;W[cf]
;B[cd]
;W[df]
;B[fc]
;W[cj]
;B[cl]
(;W[dd]
;B[cc]
(;W[eq]C[AlphaGo style invasion.]
;B[dq]
;W[do]
;B[dp]
;W[ip]
;B[jp]
;W[jo]
(;B[kp]
;W[hq]C[Good.]
;B[hp]
;W[io]
;B[gq]
;W[hr]
;B[jq]
;W[ep]C[Good]
;B[ho]
;W[co]C[Good.]
(;B[er]LB[dr:A]C[Black should descend instead, A]
(;W[fr]LB[eo:A]C[White can consider connecting at A or so, to keep the corner aji alive.]
;B[dr]
;W[hn]
;B[gn]
;W[go]
;B[gp]
;W[fo]
;B[in]
;W[hm]
;B[jn]LB[fq:B][gr:A]C[Tsurata considered white's loss of 3 stones pretty significant, while during the game I was very happy to discard them.

When I told Tsurata that one reason I was happy with discarding was that I can connect at A later, he pointed out that white B is the proper move, not A (presumably, because if white A, black can capture the three white stone in sente, while if white B instead, white can still use a ladder breaker).]
(;W[gm]
;B[gf]
;W[nc]
;B[dj]
;W[di]
;B[ei]
;W[dk]
;B[ej]
;W[ck]
;B[ek]
(;W[dl]
;B[el]
;W[dm]LB[em:A]C[I thought about this vs A; Tsurata said this is good.]
;B[dh]
;W[ci]
;B[eg]
;W[bf]
(;B[re]LB[ko:A]C[Tsurata wants black to just capture at A instead.]
(;W[qe]
;B[qf]
(;W[rd]LB[pf:A]C[Too mild, white should play A. If a fight develops on the right side, white can play a ladder breaker.]
(;B[qi]
(;W[qk]LB[qj:A]C[Better at A, ladder breaker.]
(;B[lm]
;W[pf]
;B[lc]
;W[oq]
;B[le]
;W[hk]
;B[hi]
;W[lb]
;B[kb]
;W[mb]
;B[kc]
;W[pj]
;B[mh]
;W[oh]
;B[ij]
;W[gr]
;B[np]
;W[nr]
;B[mr]
;W[bp]
;B[bq]
;W[bo]
;B[br]
;W[or]
;B[po]
;W[qo]
;B[op]
;W[qq]
;B[pm]
;W[pn]
;B[om]
;W[qm]
;B[nj]
;W[mf]
;B[lf]
;W[mg]
;B[lg])
(;B[ko]C[Just capture is best. 
This was Tsurata 4p's last comment.]))
(;W[qj]C[Should play aggressive and take advantage of the ladder.]))
(;B[pe]
;W[qd]
;B[qi]))
(;W[pf]C[White should take advantage of the ladder.]))
(;W[qf]C[White should take advantage of ladder (this move in itself is not a ladder breaker, but white should get on in the process of black trying to survive.]))
(;B[ko]C[Black should just capture now ]))
(;W[el]
;B[fl]
;W[em]C[Tsurata showed this as a variation]))
(;W[fm]C[Tsurata suggested this move.]))
(;W[eo]LB[bp:A][fr:B]C[White keeps both A and B options open this way.]))
(;B[dr]C[Proper move.]))
(;B[jq]
;W[io]C[More peaceful for black, but white is not bad this way either.]))
(;W[ep]C[Traditional way of invading here (before AlphaGo).]
;B[dq]
;W[ho]LB[co:A][jp:B]C[A and B are miai for white.]))
(;W[ej]LB[ch:A]C[it is ok for white to just defend, too, preventing black A.])
(;W[ek]C[FineArt played this in one game (the overall position may not be identical).])
(;W[nc]
;B[ch]
;W[dh]
;B[bh]
;W[di]
;B[bf]LB[cc:B][dd:A]C[This is a normal result is white lets black invade. Actually white can also make the A-B exchange just after black's invasion, as a probe.]))
