(;
AB[dd][pd][hn][ho][dp][ep][fp][gp][ip][iq][ir][cq][mq][oq][hr]
AW[in][io][go][ko][hp][hq][qp][dq][eq][gq][gr][kq][cr]
C[Black's response to the marked play?

Source:
    Go World #20, p. 42
    "From Amateur to Professional"
    Tomita Tadao 7p]
TR[cr]
(;
B[br]
C[Black, a strong amateur, wanted to make this stylish double hane.]
(;
W[dr]
C[White seemingly has to connect.];
B[fq];W[fr];B[es];W[er];B[bq]
TR[dr]
C[And Black wins this semeai.

All readers should be able to verify that after White incorrectly connects with the marked play, White has nothing better than this fatal sequence.

But White doesn't have to make the marked connection!]
)
    (;
    W[fq]
    C[White has this beautiful defensive resource!]
    (;
    B[dr]
    C[If Black continues with the obvious moves, ...];
    W[cp];B[bq];W[do]
    C[... White seems to have a hopelessly thin position.

But actually, Black cannot avoid a big loss here!]
    (;
    B[co]
    C[For example ...];
    W[fo];B[bp];W[eo];B[cp];W[hm];B[gn];W[fn]
    C[... White's capture of the center stones is a huge loss for Black.]
    )
        (;
        B[fo]
        C[Another possibility, but ...];
        W[gn]
        C[... again, Black has to give up the 2 center stones.  And Black still has other weaknesses.]
        )
    )
        (;
        B[bq]
        C[Protecting the center stones from the cut by connecting here might seem to work, but ...];
        W[jr]
        C[... Black loses the semeai for the 4 bottom stones.

As an exercise, the reader can work out the sequence for White, who wins the semeai by one move.]
        )
    )
)
    (;
    B[kr]
    C[Black sees the big problem with the previous variation, and so in the game, defends the bottom 4 stones (and indirectly the center 2 stones) here.];
    W[cp]
    C[But now White can capture the corner.];
    B[co];W[hm]
    C[An important forcing move to keep Black from extending here.];
    B[gn];W[bq]
    C[After starting against a 3 stone handicap, White is happy with this result.]
    )
)

