EVENT
BOARDSIZE 19
BLACK Ronald Schlemper
WHITE Yong-Su Yoo
KOMI 6
RESULT W+Resign
SOURCE BGJ 67, April 1986, Page 19
COM
Copyright British Go Association 1986, 1999
ENDCOM
B 1 r16
W 2 d17
B 3 d3
W 4 q4
B 5 c15
W 6 f16
B 7 c11
W 8 p17
B 9 q15
W 10 r10
MARK A@l17
COM
White 10: Schlemper expected this move at 41(A). But Yoo felt that if
Black plays next at 15, white 16, black 17, white 18*, then he has
invested too many stones at the top, especially since black can also
play a forcing move at 13.
[*BGJ had white 4 which is impossible. 18 assumed.]
ENDCOM
VAR
W 1 l17
B 2 c17
W 3 c18
B 4 d16
W 5 e17
ENDVAR
B 11 m17
W 12 k17
B 13 o16
W 14 d5
B 15 c17
W 16 c18
B 17 d16
MARK #15 \T@b17 A@b16
COM
Black 15: The 15 and 17 combination are 'kikashi' - forcing moves
which, here, strengthen black's position temporarily. If white plays 31(\t)
black can defend flexibly in a ko by playing A.
ENDCOM
VAR
B 1 d16
W 2 b17
B 3 b16
ENDVAR
W 18 e17
B 19 e5
W 20 e6
B 21 e4
W 22 f6
MARK A@f8 B@e7 C@b17
COM
White 22: A mistake, according to Yoo, because after 22-29 white
must defend in gote with 30(A), since the ladder after a black cut at B is
unfavourable. Black thus gets the big point of 31(C) first. Instead Yoo
recommends (see variation) white 24, black 29, white 25, black 27. The likely
continuation is then white 31, black C (safest given white's strength
below), white D, black 49, white 32.
ENDCOM
VAR
W 1 d7
B 2 c5
W 3 c6
B 4 b5
W 5 b17
B 6 d13
W 7 g6
B 8 h4
W 9 r14
MARK ALL
ENDVAR
B 23 d6
W 24 d7
B 25 c6
W 26 c7
B 27 b5
W 28 b6
B 29 c5
W 30 f8
B 31 b17
W 32 r14
MARK #8
COM
White 32: Important both territorially and because it revives the
'aji' (latent potential) in 8.
ENDCOM
B 33 q14
W 34 r13
B 35 h17
MARK A@o3
COM
Black 35: A mistake. This invasion is large, but white builds
central thickness and gets sente to take the last big point at 46(A).
ENDCOM
W 36 h16
B 37 j17
W 38 j16
B 39 k18
W 40 l18
B 41 l17
W 42 k16
B 43 j18
W 44 c13
MARK A@b13
COM
White 44: Ideal timing. Black must submit
with 45(A) because of white's strong wall. If he tries to resist with 1
in the variation to move 45, he loses the fight.
ENDCOM
B 45 b13
VAR
B 1 d12
W 2 d14
B 3 e14
W 4 d15
B 5 e15
W 6 e16
B 7 c16
W 8 e13
B 9 d13
W 10 c14
B 11 f14
W 12 b15
B 13 b18
W 14 d18
B 15 b12
W 16 b14
B 17 b19
W 18 b16
MARK ALL
COM
If black resists with 1, white sets up a semeai
which he wins by one move. Note that white 16 is necessary otherwise
black cuts there and wins the fight.
ENDCOM
ENDVAR
W 46 o3
B 47 g17
MARK A@g16
COM
Black 47: A small mistake. This move is 'aji keshi' - erasing one's
own potential. Black loses the chance to play 48(A) himself.
ENDCOM
W 48 g16
B 49 h4
W 50 s17
MARK #8 #32
COM
White 50: The follow-up to 32; the stone can connect to either 8 or
32.
ENDCOM
B 51 r17
W 52 s16
B 53 s5
MARK \T@r15 A@s15
COM
Black 53: A standard way of invading white's moyo, but a serious
blunder of omission. Black should first force with 60(\t), white A for
reasons which will become apparent.
ENDCOM
VAR
B 1 r15
W 2 s15
B 3 s5
ENDVAR
W 54 r4
B 55 s4
MARK A@s3
COM
Black 55: Also aji keshi; Black loses ko threats and the chance to
play 56(A).
ENDCOM
W 56 s3
B 57 s2
W 58 r3
MARK B@t3 C@m3 D@q2
COM
White 58: Descending to B leaves too much bad potential in the
corner. For example a black stone at C is virtually sente because of the
possibility of D.
ENDCOM
B 59 r8
W 60 r15
COM
White 60 exploits black's*
failure to play here. Black is on the spot. He can hardly connect at 1
in the variation to move 61, since after 2-5 the two marked stones
have become completely redundant, and later A-D overconcentrates black
still further. But 61 leaves some very nasty aji in black's position
that Yoo skilfully exploits.
[ * BGJ had "white's"]
ENDCOM
B 61 r18
VAR
B 1 q16
W 2 r18
B 3 q18
W 4 s18
B 5 q17
MARK A@q19 B@p19 C@r19 D@p18 ALL \T@r17 \T@r16
ENDVAR
W 62 p8
B 63 q9
W 64 o10
COM
White 64: 'Attack with keima' says the proverb.
ENDCOM
B 65 r11
COM
Black 65: A standard 'tesuji' in this position
to extricate one's stones and well worth learning. If White replies with
1 in the variation to move 66, black breaks out in the sequence to 10.
ENDCOM
W 66 n17
VAR
W 1 q10
B 2 s10
W 3 s9
B 4 r9
W 5 s11
B 6 p10
W 7 q11
B 8 p11
W 9 q12
B 10 p9
MARK ALL \T@r11
ENDVAR
B 67 n16
W 68 m18
B 69 n18
COM
Black 69: May have been better at 70. The semeai
in the variation leaves black two liberties ahead, although
white may have other options. Black now has great problems looking after
his weak group because of all the forcing moves white can make at the
top.
ENDCOM
VAR
B 1 o17
W 2 n18
B 3 m16
W 4 o18
B 5 p16
W 6 p18
B 7 f18
W 8 e18
B 9 f17
W 10 e16
B 11 k19
W 12 h19
B 13 f19
MARK ALL
ENDVAR
W 70 o17
B 71 m19
W 72 q11
B 73 o9
W 74 p16
B 75 o14
W 76 q16
B 77 o18
MARK E@q18
COM
Black 77-83: Best, but white can start a large ko in the corner
(with E).
ENDCOM
W 78 p18
B 79 p15
W 80 s18
B 81 q19
W 82 p19
B 83 s19
MARK E@q18
COM
Black 77-83: Best, but white can start a large ko in the corner
(with E).
ENDCOM
W 84 n9
B 85 s11
W 86 q10
B 87 s10
W 88 q13
B 89 l19
PRISONER l18 m18
MARK A@r7 F@l3
COM
Black 89: The losing move. It eliminates the ko, but the bottom
group now falls under a fatal attack. Black must defend at 91(A), white will
start the ko, but black can take a large point such as F in
compensation, and the game would still be close.
ENDCOM
VAR
B 1 r7
W 2 q18
B 3 l3
W 4 r19
PRISONER q19
ENDVAR
W 90 s7
B 91 r7
MARK A@s8
COM
Black 91: The only chance now is to play at 94(A), but after white 91,
black loses half his group and white will end with sente to play on the
lower side.
ENDCOM
VAR
B 1 s8
ENDVAR
W 92 s6
B 93 r6
W 94 s8
B 95 o6
W 96 p9
B 97 r5
W 98 s9
B 99 r9
W 100 r12
B 101 p5
W 102 n5
B 103 n6
W 104 m6
B 105 m5
W 106 n4
B 107 m7
W 108 l6
B 109 n8
W 110 m9
B 111 l7
W 112 k6
B 113 k7
W 114 p7
MARK #91-114 A@j6 B@b14 C@l3
COM
White 91-114: White's attack has put him clearly in the lead. 114
is actually bad - he should extend to 115(A). But Yoo seems to have counted
that this capture, together with the large yose at 118(B) and 128(C), is
enought to win.
ENDCOM
B 115 j6
W 116 q5
B 117 l4
W 118 b14
B 119 c14
W 120 b12
B 121 d13
W 122 c12
B 123 d12
W 124 b11
B 125 d11
W 126 c10
B 127 b15
W 128 l3
B 129 k3
W 130 l2
B 131 k2
W 132 m4
B 133 k5
W 134 k1
B 135 j1
W 136 l1
B 137 h2
W 138 b7
B 139 d10
W 140 c9
B 141 b18
COM
Black 141: A last desperate attempt to get something from an attack
on white's top group. But ...(see move 160)
ENDCOM
W 142 g13
B 143 j13
W 144 g11
B 145 h12
W 146 g12
B 147 j10
W 148 l13
B 149 l14
W 150 m14
B 151 m13
W 152 k14
B 153 l15
W 154 k13
B 155 m12
W 156 m11
B 157 j11
W 158 l12
B 159 o12
W 160 j8
COM
White 160: ... White easily refutes it.
ENDCOM
B 161 k9
W 162 e14
B 163 d14
W 164 k8
B 165 l8
W 166 j9
B 167 g9
W 168 g8
B 169 l9
W 170 k10
B 171 h10
W 172 h9
B 173 k11
W 174 l10
B 175 g14
W 176 h14
B 177 g10
W 178 f10
B 179 j14
W 180 k15
COM
White wins by resignation after 180.
ENDCOM