The last few weeks were devoted to tactical issues, involving a lot of reading. However, tactics should always be part of the strategy. This week we are lucky to have a game that exemplifies how tactics--setting up, breaking and maintaining a ladder--and strategy are intertwined. It concerns the fourth game of the Gosei Title between defender Koichi Kobayashi and challenger Norimoto Yoda, the Meijin titleholder. Since this is a best-of-five match, the first to win three games wins. The Meijin won the first two games and 50-year-old Kobayashi looked like a goner. However, the defender showed amazing resilience and won the third and fourth game. The challenger won the fifth and final game, regaining the title, worth 7.77 million yen, for the first time in five years.

Diagram 1 (1-27): Until 9 there are no problems. It was possible for Black to play at 9 right away without first exchanging 7 for 8. This exchange actually involves an invisible ladder. See Reference 1. White 10 and 12 form an approach as well as a ladder breaker. That is the reason Black invades at 13, followed by the joseki (standard exchange) to 21. White then gets sente to first turn to 22 to reinforce his weakest group with 24. This is again sente as Black has to defend with 25 against an invasion at A.

In the end, White uses the sente he acquired after the exchange in the upper left to invade at 26. This move also involves a ladder, which becomes apparent in the sequence that follows. Instead of immediately answering at 27, Black could have first made the exchange C for white D, which would invalidate the sequence in the game.

Reference 1: White likes to play at 1, but he is at a loss when Black wedges in at 2. The only way White can get a good result is by cutting and connecting with 3 and 5. However, at this point, Black can set up a ladder with 6. White 10 and 12 in Diagram 1 combine to break this ladder and it is the reason Black invades the corner with 13.

Diagram 2 (28-47) (black 35 is where the marked white stone is): Since Black had not forced the 37 for A exchange, White could wedge in with 28 to invoke a ladder. Since Black resists with 29 through 35, White can capture Black's marked stone in a ladder. This looks terrible for Black. However, Black has a greater plan that becomes apparent when he plays at 37, a ladder breaker. He hopes White will answer at A as he can then pull out his marked stone. See Reference 2.

White's next move took the pros analyzing the game by surprise. Yoda played at 38, which keeps the ladder intact and attacks black 37 as well.

Black, on the other hand, splits White's position and takes a lot of profit with the exchange through 47. So, where should White play next? He has cutting points at A, B, and C, and these weaknesses combined with Black pulling out his marked stone at D guarantees a tough fight. Can White play at E to collectively defend against any attack while attacking the black group around 31?

Reference 2: If White answers black 1 with 2 to keep his marked stones connected, Black plans on pulling out his marked stone with 3, etc. If White insists, he'll find out the hand way, black 1 is a ladder breaker. That is the reason, White answers at black 17 (in this diagram) in the actual game (move 38 in Diagram 2).

Diagram 3 (48-59): White 48 is a strong move. It safeguards the corner territory while attacking Black's eye-space while also inviting Black to cut at A, white 66, black 54. This would protect Black's stones, but such a meek approach is beneath Kobayashi. He completely ignores his attacker and presses with 49 through 53 to build influence in preparation for the coming center fight. 54 is White's follow-up, but in the end, he has to come back with 60 and 62. Black now grabs his chance to play, 63 and 65, which is a ladder breaker again. White has little choice but to submit with 66 and Black captures three white stones with 67 and 69. Black has completely deflected White's attack. In the end, he wins by just half a point.

New Problems

Problem 1: How can Black kill the white group?

Problem 2: Where should Black play to make his group alive?

Solutions

Solution 1: Black 1 is the vital point. White 2 captures the marked stone but eventually, White will have to connect there so this is not an eye. Black has time to play at 3 reducing White's space to one eye. White dies.

Solution 2: Black 1 is the correct move to make two eyes. With correct defense at 3 and 5, A and B are always two eyes.

Want to find out more? Come to Ben's Cafe in Takadanobaba (03-3202-2445 or www.benscafe.com), where the English-speaking go community congregates every Sunday starting at 11 a.m. You can enjoy free lessons until 1 p.m.

Van Zeijst is a four-time European go champion and European representative at the Fujitsu World Championship.