British Go Journal No. 67. April 1986. Page 22.

Interpolis Match – Game 2

Game 1 is on page 19.

You might wish to open a second window beside the first one to view Fig 1 whilst reading the text in the first window.

Black: Yong-Su Yoo
White: Ronald Schlemper
Komi: 6
The game-file in Ishi and SGF format.

Figure 1 (1-100)

• White 6: Yoo had expected this move.
• Black 7: An agressive move that leads to early fighting.
• White 14: Usually played at 16.
• Black 15: Essential, otherwise white can extend towards 1 and make a comfortable base.
• White 16-28: An old fashioned joseki.Note the similarity of black 19, which allows him to capture a stone in sente, to white 50 in game 1.
• Black 29: This was apparently described by Schlemper as a 'typical' overplay by Yoo. Better, in his view, would have been to play at 36, followed by white 46 and then 29. Another option is the shoulder hit one point above 29. In fact Yoo had not calculated the consequences of white's cut at 30, and was prepared to sacrifice the stones 7, 9 and 11 if necessary.
• White 34: The brutal option is 1 in Dia 1.
  

  Diagram 1

  After 2 and 3, black probably has to abandon his four stones. 4-12 is one possible continuation. Black builds thickness and encloses the top, while white still has some bad aji (eg at A).
• Black 41: Another 'overplay', according to Schlemper,
  

  Diagram 2

  but he shys away from trying to punish it by pushing and cutting at 1 and 3 in Dia 2. After 4-7 a complicated fight in the centre would ensue.
• White 46: White would love to play A [in Fig 1] , but after black B his group at the top would be in trouble.
• White 50: A serious mistake, this move is too early. In the coming sequence Black's centre group is much strengthened, white loses all his territory at the top, and black 67 becomes sente. White should have played at 63 or just turned elsewhere.
• White 68: A painful necessity.
• Black 69: How should black defend the right side? According to Schlemper, a professional would never play this move and permit white 73. If white invades at the 3-3 point, black's extra thickness would let him launch a severe attack on White's group. Yoo apparently thought it neither here nor there, whether a professional would play 73. He couldn't bring himself to play such a 'slow' move. His idea is to invite 73, then cut at 1 in Dia 3. Although 'bad style' (if the 'proper' cut at 2, white can get a ladder after 1) this cuts white into two weak groups. The moves to 25 are one possible continuation.
• White 72: White avoids the fight, but will have to make a lot of territory at the bottom to have a chance.

Diagram 3

Figure 2 (101-200) BGJ did not detail these moves, sgb's guesses 154 ko at 148, 160 at 127, 161 ko at 151, 164 at 148, 167 at 151, 169 at 148.

• Black 109^* loses three stones, but leaves white with dreadful aji in the corner, which Black exploits with 109-11, putting him ahead. If White plays 116' at 119, then black 117, white takes, black 116, white connects, black plays one point below 115, and lives.
  [*BGJ had Black 89.]
• White 124: White's only chance is to pull something off on this side.
• Black 129: A mistake. Yoo felt White's efforts were doomed to failure and so decided to swallow all his stones. It transpires that black would be safer to follow Dia 4.
• Black 139: Forced, else Dia 5 follows and black loses the fight.
• White 140: A fatal error. White misses a tesuji at 141. Black's best move then is 1 in Dia 6. But after white 2, black 3 fails: in the forced sequence to 16 black loses the fight by one liberty. So black must play 3' at 6, then white 3 and black takes. White's biggest ko threat is at 8 , black captures (at 149 in Fig 2), white plays 10 and lives. Black then has sente to play, eg at A, and the game is still undecided.
• White 168: Not big enough. Black will connect wherever white plays.
• Black 171 and 173: He submits in order to play at 181 (worth 8 points in reverse sente). After this move black cannot be overhauled. (Note however that 177 was a bad exchange for 178.)

Diagram 4

Diagram 5

Diagram 6

Figure 3 (201-266) BGJ did not detail these moves, sgb's guesses 222 at ?, 237 at ?, 248 at , 249 at , 259 at ?, 260 at ? , 261 at ?, 263 at ?, 264 at ?.

Black wins by 6 points.

By now Schlemper must have been regretting his lack of preparation. However his fortunes recovered in the third game.