Many players think the game is over at ...

By Rob Van Zeijst

Some people are wondering if such board games as go and chess will be accepted as Olympic sports. The answer appears to be yes. On May 20, the General Association of International Sports Federations granted membership to the International Go Federation, which has 66 member countries. Go is expected to be given observer's status for the 2008 Beijing Olympics and gain full participation in the 2012 Games. There is a downside, however. Some players are opposed to the mandatory drug tests.

Double sente

Moves that are sente (keeping the initiative) for both sides are called double sente. The problem is the timing as other moves may be more important.

Diagram 1: Many players are familiar with this joseki after White invades at 1. After black 8, White's corner is alive. Why then does he exchange 9 and 11 for 10 and 12?

Diagram 2: If White fails to make this exchange, Black will immediately play at 1 and 3, forcing white 2 and 4. White has to answer Black's moves, otherwise he dies. This hane-tsugi, a combination of a diagonal stone and a connection, is sente for both sides and the difference in territory is substantial.

Solutions to last week's problems

Solution 1-A: Black 1 and 3 are sente, because White has to answer with 2 and 4 (or A) to protect his territory.

Solution 1-B: However, it is more likely that White will play 1 and 3 in sente to force black 2 and 4. Why? Because Black loses more than White (in Solution 1-A) if he doesn't respond to White's moves. The difference between Black playing first and White playing the first move is four points.

Solution 2-A: White 1 will probably be answered by 2 and it is likely Black will reinforce his position with 4 after white 3.

Solution 2-B: White 1 looks good. After black 2, white 3 and 5 appear to be strong moves, but after 6, White is left with two choices A and B. Both have disadvantages. Also, the exchange C for D becomes less obviously sente for White.

Solution 2-C: What if White plays at 3 right away? Probably Black will connect with 4, giving White the opportunity to play a sente move with 5. But before answering with 8, Black probably will exchange 6 for 7. Later on, Black can cut off the marked stone with A, followed by white B, black C and white D. However, the best move depends on the rest of the board.

Solution 2-D: What if Black connects with 2? White will then dig in further with 3. If Black resists with 4, white 5 and 7 will help ensure life for White in the sequence up to 11. Black can connect with 12 but he is doomed when White plays at 13.

Solution 3-A: After white A, white B and black C, Black needs to defend. Black 1 may prove better than D. If he doesn't do anything, what will happen then?

Solution 3-B: If Black does not make any defense, White's clamp at 1 will prove dangerous. Black 2 prevents White from connecting underneath but white 3 poses a lot of problems. Black's strongest move is 4, but white 5 through 11 will kill the entire Black corner.

Conclusion: The endgame requires a lot of reading just to gain an advantage of one or two extra points, but it is usually well worth the effort.

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

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