(;
AB[oc][ld][qd][qc][qj][qg][ip][cp][do][fo][fm][em][fl][fk][fj][di]
AW[ci][dh][cg][dd][jd][rd][qe][rc][pp][cr][eq][gp][dm][dl][el][gk]
TR[rc]
C[Black's response to the marked push?

Source:
    3rd Kisei Title game 5, Fujisawa Shuko (B) vs. Ishida Yoshio (W)
    Go World, Vol. 14, p. 14]
(;
B[rb]
C[Black should have played the hane here.];
W[qf]
C[White has no choice but to follow this sequence.];
B[pg];W[of];B[nd]
C[Snf Black should be able to use this attack against the upper right group to build up center influence.]
)
    (;
    B[qb]
    C[A bit slack.]
    (;
    W[qf]
    C[Perhaps Black expected this response, in which case, ...];
    B[rf]
    C[... Black has the following sequence.];
    W[re];B[rg]
    C[With only one gote eye in the corner, White has to run out into the center, while Black builds center influence. ]
    )
        (;
        W[rf]
        C[Shuko's unexpectedly good response.]
        (;
        B[rg]
        C[Black can block here, but ...];
        W[qf];B[pg];W[se];B[rb];W[oe]
        TR[rb]
        C[... White's result is much better than if Black had played the earlier variation starting with the marked hane.]
        )
            (;
            B[pe]
            C[In light of the previous variation, Black in the game decided to go all out for central thickness.];
            W[qf];B[pf];W[rg];B[qh];W[jf]
            C[But in the game, now White has sente to take this obviously large point that negates some of Black's center influence.];
            B[se]
            C[Note that Black cannot kill the upper right group.

This position is a must-know tsumego classic.];
            W[rh];B[ri];W[sh]
            (;
            B[sf];W[rb];B[ra];W[sb];B[sd];W[re]
            C[White is alive in seki.]
            )
                (;
                B[rb]
                C[A mistake.];
                W[sf];B[sc];W[re]
                C[Now White lives with territory.]
                )
            )
        )
    )
)

