(;
EV[Oza]
DT[2015-11-30]
PB[Michael Redmond]
BR[9P]
PW[O Meien]
WR[9P]
KM[6.5]
RE[W+3.5]
C[64th Oza preliminary
White:  O Meien 9P
Black:  Michael Redmond 9P
Commentary:  Michael Redmond 9P
Published in the March 1, 2016 edition of the American Go E-Journal

I have Black against O Meien 9P in this game.  In a fight within White's moyo, I was successful, up to a certain point...];
B[qd];W[dd];B[pq];W[po]
LB[np:A]
C[If Black plays elsewhere and White continues with A, there are ladder variations in the following fight.  Because of that, there is some merit in playing this kakari with a White stone in the upper left corner.];
B[qo];W[pp];B[qp];W[oq];B[qq];W[pn];B[dp]
LB[qm:A]
C[The open corner is bigger than continuing at A.];
W[oc];B[pe];W[qn];B[or];W[nq];B[nr];W[mq]
C[The local position in the lower right corner favors White.  In the overall position, White's wall is badly placed and difficult to make use of, so I call this result even.];
B[kc]
(;
W[le]
C[Now White needs to move out on the upper side to make use of his thickness.]
(;
B[fc]
C[In this opening, I feel that I want to avoid a fight.  The variation shows the move that I also considered.];
W[lc];B[kd];W[ld];B[pc];W[id];B[cf];W[df];B[dg];W[ef];B[cc];W[ce];B[dc];W[hc];B[gd];W[he]
LB[je:A]
C[White's kosomi is awkward shape, but he needs to play here to prevent Black from moving out at A.];
B[ge];W[cg];B[cn];W[ph];B[ob];W[hf];B[eq]
C[Black has four corners, and White has a moyo.  I don't know which side has a better position, but my guess is that it is about even.];
W[hp];B[ck];W[cq];B[cp];W[bd];B[bc];W[og]
LB[pj:A]
TR[ck]
C[White needs a move here to prevent Black's invasion at A.

M:  if Black could not invade at A, then White would play on the lower left to set up a moyo that would be a serious problem for Black?  If so, then Black would not have had time to play the "leisurely" marked move.];
B[lg]
LB[ke:A][nf:B]
C[This capping move looks at the aji of Black A, and the connection at B.

M:  another weakness that Black must have planned on exploiting several moves before.];
W[dl];B[ch];W[bf];B[fl]
C[M:  nice counter-attack idea.];
W[dk];B[cl];W[dm];B[cm];W[hl]
C[White is building a moyo in the center.  White's move here is also a ladder breaking move for the upper side, as the variation for Black's next move shows.]
(;
B[hn]
LB[nf:A]
C[Black can break through at A, so my idea here is to reduce White's moyo from above and below.];
W[nb];B[nc];W[mb];B[od];W[nf];B[il]
(;
W[im]
C[White needs to play aggressively now.  See the variation.];
B[hm];W[hk];B[jl];W[in];B[io];W[jn]
(;
B[ij]
C[See the variation.];
W[ho];B[fn]
LB[io:A][jn:B]
C[Even though A is cut off, Black's stone has some aji, and the exchange with White B was a kikashi.];
W[fk];B[lj];W[kh];B[ki];W[jh];B[ji];W[ih];B[lm];W[jo];B[ok]
C[The game is still undecided.]
(;
W[ml]
C[White's move here is an overplay, and could have been the losing move.  See the variation.];
B[nm]
C[Black can squeeze to make good shape in the center.];
W[nl];B[ol];W[mm];B[mn];W[nn];B[om];W[ln];B[mo];W[ll];B[km]
(;
W[kl]
C[See the variation.];
B[jm];W[lo]
C[I was rather proud of myself at this point, because this squeeze is going to give me a winning position.]
(;
B[kk]
LB[no:A]
C[I forgot to play the atari at A!  This mistake is the losing move.  See the variation.];
W[no]
LB[lh:A][no:B]
TR[lg]
C[Now Black cannot squeeze with sente, and cannot save the marked stone with A.  Black's mistake of not first playing atari at B lost one move, which in this case is about 15 points in territory.  Now White will win by a few points on the board.];
B[oi];W[lh];B[qj]
(;
W[er]
C[This move complicates the game unnecessarily, and starts a series of trades in which White takes the lower left corner, both the left and lower side territories disappear, and Black gains territory on the right side.  In all, I gain a few points, but not enough to turn the game around.

See the variation.];
B[fr];W[dr];B[bp];W[fq];B[gq];W[fp];B[gp];W[gr];B[hq];W[ip];B[fs];W[gs];B[go];W[bq];B[iq];W[es];B[bh];W[mp];B[mi];W[gm];B[gn];W[gl];B[mr];W[ap];B[fr];W[ep];B[jp];W[dq];B[rh];W[gb];B[fb];W[an];B[lq];W[kp];B[jq];W[rn];B[rl];W[mn];B[qg];W[al];B[bj];W[ed];B[ec];W[ac];B[ab];W[ad];B[ba];W[sq];B[gc];W[hb];B[sr];W[dh];B[dj];W[eg];B[fm];W[ej];B[di];W[hj];B[ei];W[ik];B[jk];W[ii];B[fj];W[ek];B[rm];W[so];B[rr];W[js];B[io];W[ak];B[dn];W[fi];B[fh];W[gj];B[eh];W[pi];B[pj];W[mh];B[nh];W[pf];B[ng];W[mg];B[oh];W[pg];B[qf];W[gh];B[bg];W[fg];B[ne];W[of];B[af];W[ls];B[dg];W[cf];B[gf];W[gg];B[ms];W[aj];B[cd];W[be];B[ai];W[nj];B[nk];W[mj];B[mk];W[li];B[oj];W[kj];B[lk];W[jj];B[bo];W[ao];B[eo];W[mc];B[hd];W[ic];B[na];W[ma];B[oa];W[qi];B[ri];W[pm];B[pl];W[qm];B[ql];W[fa];B[ea];W[ga];B[on];W[oo];B[fe];W[ee];B[dh];W[sm];B[sl];W[em];B[sn];W[ro];B[sm]
C[White wins by 3.5 points.]
)
    (;
    W[gq]
    LB[eo:A]
    C[White has this easy way to win.  White threatens to cut Black off with A.];
    B[fq];W[mr]
    C[White is ahead on the board.]
    )
)
    (;
    B[no];W[on];B[kk];W[mp];B[nk];W[np];B[lh];W[qj];B[qk];W[rk];B[pj];W[qi];B[gq];W[hq];B[gr]
    LB[lg:A][ne:B]
    TR[lh][rk][qj][qi]
    C[After the squeeze, Black's marked play saves the stone at A, a big move.  And White's marked moves are necessary because without these moves, a Black play on the right side would force White to connect at B.

After this move, Black is ahead by more than 10 points on the board.]
    )
)
    (;
    W[mj]
    C[White cannot break through in the center.];
    B[mk];W[nk];B[nj]
    C[White collapses.]
    )
)
    (;
    W[nl];B[nk];W[mk];B[mj];W[ml];B[ol];W[mn]
    C[Black is not alive yet.  While attacking, White has potential to catch up in territory, and this looks like it could be a close game.]
    )
)
    (;
    B[ho]
    C[I was tempted to continue taking profit on the lower side, but the following sequence looks dangerous.];
    W[jo];B[ip];W[jj]
    C[White's center is too big, and making life in the center looks difficult for Black now, so I rejected this variation.]
    )
)
    (;
    W[ik];B[jl];W[hk];B[jn];W[kj];B[ll]
    C[White doesn't have enough space to catch up to Black's lead in territory.]
    )
)
    (;
    B[ke];W[kf];B[lf];W[mf];B[mg];W[nf];B[jf];W[kg]
    C[The ladder favors White.]
    )
)
    (;
    B[nd];W[lc];B[ld];W[md];B[kd];W[me];B[mc];W[nc];B[lb];W[od];B[oe];W[ne];B[qh];W[gc];B[cj]
    C[Which side is ahead is difficult to judge.  I now think that this is better than the game for Black.]
    )
)
    (;
    W[pi];B[nd]
    C[When Black gets a strong position in the upper right, White will have trouble controlling the center, and the lower right White wall will become inefficient.]
    )
)

