(;
AB[bb][cc][db][fc][fe][gf][hf][he][id][jd][kd][pd][qd][od][oc][pb][qb][qi][pj][pk][ok][ol][oi][nj][mj][pp][qp][qo][ro][op][mo][iq][fq][dr][gj]
AW[mb][nc][ob][na][pc][qc][lc][jc][ic][hc][hd][gd][ge][fd][eb][dd][df][dc][da][cq][dp][cn][lk][mk][nk][lj][li][ni][ij][il][rq][qq][rp][pq][oq][qn][mq]
TR[da]
C[Black's response to the marked play?

Source:
    American Go Journal, Vol., No. 2, pp. 23-25
    Rui Naiwei 9p vs. Lee Changho 9p
    Commentary:  Rui Naiwei 9p];
B[bf]
C[Correct.  Black cannot win the ko, so Black runs out.  This move is one of two moves than Rui really liked in this game.]
(;
W[bh]
C[White has no choice but to block to keep Black from extending down the right side.

Black is ahead in the game at this point, but ...]
(;
B[cb]
C[... Black carelessly connects immediately.];
W[bd]
C[White splits the corner stones.  Now the game is close.]
(;
B[ec]
C[A few more moves from the game follow.];
W[fb];B[ed];W[cd]
C[Nice move.];
B[ee];W[gc];B[eg];W[cf]
C[White (Lee Changho) went on to win the game.]
)
    (;
    B[cd]
    C[Note that Black's push here still doesn't capture the left side stone.];
    W[be];B[ce];W[cf];B[de];W[ed];B[ee];W[dh];B[fg];W[ej]
    TR[bf]
    C[The game would still be close, but losing the marked stone was big.]
    )
)
    (;
    B[bg]
    C[Rui said she should have forced here first, which is normal.];
    W[ch]
    C[White has to stand up here.];
    B[cb]
    C[And now Black can come back here to connect.  Black lives and has corner territory.  The game would be hard for White.

Compare this position with the game line.]
    )
)
    (;
    W[cb]
    C[White cannot capture here, because ...];
    B[cj]
    C[... extending here would finish the game quickly in Black's favor.]
    )
)

