(;GM[1]FF[4]SZ[19]AP[SmartGo:2.8.3.0]CA[shift_jis]
GN[SAWMG 2012 pairGo final]
PW[Weijie Jiang, He Li]WR[9P, 2P]
PB[Chulhan Choi, Jeong Choi]BR[9P, 3P]
EV[SAWMG Pair Go]RO[3 ]
DT[20121219]
KM[7.5]
RE[B+R]
US[www.cyberoro.com]WT[China]BT[Korea]
AN[Michael Redmond 9P]
C[SAWMG Pair Go: Final Round
W: Weijie Jiang, He Li (China)
B: Chulhan Choi, Jeong Choi (Korea)
Commentary: Michael Redmond 9P
Edited by Chris Garlock

This is another high-level pair go match that's virtually indistinguishable from a regular one-on-one game. As in the second-round game between China and Japan, the outcome of the game is determined by the fight in the center, and, also as in that game, there's a late-stage turn of fortune that's decisive. ]
MU[1];B[pd];W[dd];B[qp];W[dp];B[fq];W[cn];B[lq];W[qf]LB[qj:A]
C[In this tournament we've been seeing white playing at A a lot, but this is also a common move]
;B[pi];W[nd];B[pf];W[qc];B[qe];W[pc];B[ld]LB[oc:A]
C[with this, black is always looking at the aji at A];W[nf];B[qg];W[gc];B[fo]
;W[dk]
C[B (C16) is the move I'd usually expect (see var) ]
(;B[cf];W[ce];B[df];W[dh];B[ff];W[ee];B[ef];W[ge];B[fe];W[fd];B[eh];W[di]
;B[hg];W[if]
C[white's hoping to enclose the upper side as the left-side black group escapes]
;B[ig];W[jf];B[lf]
C[black can't afford to give white the whole upper side];W[jg];B[lh];W[ih]
C[turning at B (H12) looks like the normal move (see var)]
(;B[gj]LB[hh:A][ii:B]
C[a very light move; black apparently doesn't like the black A, white B exchange, which would strengthen white in the center]
;W[eq];B[fr]LB[cq:A]
C[the exchange of w42 for b43 lessens the size of the invasion at A];W[op]
;B[pn];W[qq];B[rq];W[on];B[om]LB[rp:A]
C[the tesuji is a white cut at A now, but in recent games a new variation has been seen, in which the w46, b47 exchange becomes kikashi...]
;W[po];B[qo];W[pm];B[qn];W[nn];B[ol]LB[pq:A]
C[having played the 46-47 exchange before the forcing moves above is key, because if white attached at 46 now, black would answer at A instead, capturing the one stone]
;W[pq]LB[qq:A];B[rr];W[kn]
C[since white doesn't have space for eyes on the side, it's correct to play from above]
;B[jp];W[ml]
C[the territories are more or less balanced at this point

there are three unsettled groups on the board: the upper left black group, the upper side black group (black 15/37/39), and the white group in the lower right. but neither side can afford to play defensively, as the balance of the game depends on who gets an advantage in the center fight]
;B[lm]LB[mm:A][ln:B]
C[Since A and B are miai, white would prefer to find a way to avoid the necessity of playing either]
;W[kp];B[kq];W[lp];B[jo];W[mq];B[mr];W[mp];B[nr]
C[the exchange starting with white 62 enables white to connect w58 to his group]
;W[kk];B[jl];W[ok];B[pk];W[oj];B[pl];W[km]
C[black can escape by pushing out at B (M8) but it just helps white connect out and surround the upper side black group (see var)]
(;B[cc]
C[black's jump into the corner gives black a potential ko, but that would be dangerous to the outside black group]
;W[cd];B[bf]LB[bc:A]
C[black threatens tomake a life in the corner with A];W[bc];B[cq]
C[blocking at B seems natural, but the difference in territory between that and the game sequence is small, and white saw some advantage in splitting black into two groups]
(;W[er];B[bo];W[co]
C[Crawling at B (B6) doesn't work (see var)]
(;B[bp];W[bn];B[br];W[bh]LB[oc:A]
C[takes away a black eye on the side and completes the white territory. the territories are still fairly balanced but white seems to be taking the offensive in the center. white does have some bad aji at A, so as they attack black in the center, white should try to erase this weakness.]
;B[mj];W[fi];B[gi];W[fh];B[gf];W[ij];B[hh];W[kh];B[he];W[gd];B[hf];W[jd]
;B[hl];W[im]
C[as white's attack on the upper left side group continues, we see black's lower side group becoming thin. provided white returns to protect the upper side later, white seems to have a lead.]
;B[fl];W[in];B[dl];W[cl];B[ek];W[ej];B[ck];W[dj];B[li];W[gm];B[jk];W[jj]
;B[hk];W[kl];B[en]
C[black connects their center group];W[gp];B[fp];W[dm];B[gn];W[ho];B[hq]
;W[el];B[fk];W[hi];B[gh];W[nc]
C[white has about 50 points and black has a bit more than 50, but white will win with komi]
;B[lb]LB[jb:A]
C[white must protect at A];W[hm]
C[this is supposed to be forcing against the black center];B[ic]LB[kj:A][jb:B]
C[with the cut and A, this threatens white's center group, so black can ignore W130 and scoop out the upper side. If white bad played at B, the upper left corner territory would have been 23 points; but after this move, it's only about 16, a 7-point difference that just about cancels the komi]
;W[id];B[jc]
C[cutting at B (F7) doesn't work (see var)]
(;W[le]
C[as they prepare to attack the black center group, white wants to create another escape route for their center group (see var)]
(;B[me];W[ke];B[md];W[mf];B[mg];W[hc]LB[hd:A][kj:B]
C[now A and B are miai so black must protect his center group];B[fm];W[ne]
;B[nb];W[ob];B[hb];W[gb];B[kc]
C[If white allows black to live while taking profit on both sides (see var), I think white has a small lead (1.5 points in the variation I used to estimate the score).]
(;W[mc];B[mb];W[na]
C[this is the tsumego tesuji];B[ha];W[jb];B[ja];W[ka];B[ib];W[ia]
C[though this is a hanami (one-sided) ko, white is losing a lot of territory when they lose the ko]
;B[ki];W[ji];B[ja];W[ng];B[nk];W[ia];B[kj];W[hd];B[ja];W[gq];B[gr];W[ia]
;B[nq];W[np];B[ja];W[cs]LB[iq:A]
C[white has ko threats at A (at least 2), but black also has threats against the lower right center group, so taking this corner seems to be the best that white can do. 

]
;B[kb];W[bs];B[rd];W[rc];B[pp];W[oo];B[ga]LB[eb:A]
C[Despite gaining more than 20 points in the lower left corner, assuming a white play at A, white has lost 15 points on the upper side alone, and black got the large endgame move at b175. the ko fight has turned the game around and black now has the lead. ]
;W[hp];B[do];W[cp];B[ip];W[ni];B[nl];W[iq];B[hr];W[mk];B[nh];W[oh];B[mh]
;W[ph];B[qh];W[qi];B[pj];W[oi];B[og];W[pg];B[of];W[rf];B[nj];W[re];B[qd]
;W[sd];B[mi]
C[after the game, the players were looking at the variation starting at B (S12), but it still looks like a comfortable black win ]
(;W[od];B[es];W[ds];B[pe];W[oq];B[rg];W[db];B[fs];W[dq];B[eb];W[ec];B[da]
;W[fb];B[fa];W[ea];B[lk];W[ll];B[eb];W[lr];B[kr];W[ea];B[sc];W[sb];B[eb]
;W[kd];B[lc];W[ea];B[nm];W[mm];B[eb];W[cb];B[sf];W[kg];B[lg]
C[if white leaves the upper right corner, black can get a seki (see var)]
(;W[oa];B[qs];W[or];B[os];W[hj];B[bg];W[ah];B[ch];W[ci];B[dg];W[be];B[ea]
;W[fg];B[eg];W[gl];B[gk];W[cg];B[ae];W[ad];B[em];W[dn];B[dl];W[bk];B[se]
C[white resigns. ])
(;W[ea];B[ra];W[qb];B[pa];W[oa];B[qa]))
(;W[rh];B[rg];W[sg]LB[pe:A];B[ri];W[pe];B[sh];W[od];B[db];W[bb];B[es];W[ds]
;B[fs];W[dq];B[oq];W[fb];B[fa];W[eb];B[ea];W[dc];B[cb];W[ba];B[da];W[be]
;B[kg];W[jh];B[bg];W[ah];B[ch];W[ci];B[dg];W[fg];B[ag];W[bi];B[ae];W[ad]
;B[eg];W[hj];B[ma];W[oa];B[nm];W[mm];B[lk];W[ll];B[ko];W[lo];B[em];W[gl]
;B[gk];W[dl];B[de];W[ed];B[sf];W[ie];B[go];W[dn];B[eo];W[cg];B[af];W[ch]
;B[lj];W[se];B[sg];W[jn];B[jq]))
(;W[mb];B[mc];W[na];B[kd];W[ib];B[jb];W[ha];B[ja];W[ng];B[nk];W[mh];B[lg]
;W[ni];B[nl];W[mk];B[nj];W[rd];B[nq];W[np];B[kj];W[ki];B[lj];W[hd];B[pp]
;W[oo];B[oq];W[sg];B[rf];W[sf];B[se];W[re];B[sh];W[sd];B[rg];W[se];B[qh]
;W[oi];B[pj];W[gq];B[gr];W[hp];B[ip];W[cs];B[bs];W[ao];B[ap];W[an];B[cp]
;W[do];B[es];W[ds];B[fs];W[dr];B[qd];W[rc];B[nm];W[mm];B[lk];W[ll];B[ia]
;W[hb];B[be];W[bd];B[bg];W[ah];B[ch];W[ci];B[dg];W[fg];B[eg];W[od];B[ag]
;W[bi];B[de];W[ed];B[ad];W[ac];B[ae];W[og];B[ko];W[lo];B[hj];W[ii];B[em]
;W[dl];B[pg];W[la];B[ka];W[ma];B[mi];W[kg];B[gl];W[go];B[cr];W[nh];B[ph]
;W[cg];B[kf];W[je];B[ik];W[ch];B[iq];W[hn];B[fn]))
(;B[hb];W[fm];B[hd];W[hc];B[ki];W[ji];B[kj];W[me]))
(;W[fm];B[hd];W[hc];B[ki];W[ji];B[kj]))
(;B[bn];W[bp];B[cp];W[bq];B[cr];W[br];B[cm];W[dm];B[cl];W[dl];B[ds];W[es]
;B[do];W[dn];B[eo];W[dr];B[ep];W[cs]))
(;W[cp];B[dq];W[ep];B[er]))
(;B[ll];W[kl];B[lk];W[lj];B[mk];W[mj];B[nk];W[mg];B[lg];W[ki]))
(;B[hh];W[ii];B[gj]))
(;B[cd];W[ce];B[be];W[de];B[bd];W[bf];B[dc];W[ec];B[db];W[cg]
C[not bad for white]))

