While the Nihon Kiin,

By Rob Van Zeijst

While the Nihon Kiin, Japan's national go organization, celebrated its 80th anniversary last week, Cho U, 24, celebrated the feat of becoming the youngest player in Japan's history to hold the Honinbo and Meijin titles simultaneously. This was the deciding factor for Cho to be nominated for the Journalist Club Prize for go. At the same time, the club decided to award the same prize to Cho's wife, Izumi Kobayashi. She held the Women's Honinbo and Meijin title simultaneously until last month, when she lost the latter title.

Meijin title

Cho U won the Meijin title by defeating Norimoto Yoda in the sixth game of the best-of-seven series. Cho now holds three titles: Meijin, Honinbo and Oza, although he is in the process of defending the latter title. Let's see how Cho (Black) captured the Meijin title.

Diagram 1: White 1 is a sente move that may lend support to a White invasion in the center. Surprisingly, Black does not connect immediately at 6 but counters with 4. This in an attempt to make White's stones more vulnerable to attack. However, white 7 is also a good move as it prepares to reduce Black's territory with 13 while ensuring that White's stones can only be sacrificed on a small scale.

After 8 and 9, black 10 looks like the vital point, but 11 through 15 are good countermoves. As Black cannot cut through with 17 or C, he switches to 16, etc. However, this leaves the lower edge exposed after 21.

If you count the territory, you find White has engineered a turnaround. Still, Black 24 is worth many points. There is no margin for error for either side. However, White blows his lead when he plays at 41. At this point, he should have played at 53. Then if Black defended at 54, this would have been followed by white 43 and black 52, leaving White with the possibility of cutting off Black's center group with a ko at A. But with the 41-for-42 exchange, he cannot start the ko now. If White played at A, black would respond with B, and Black would capture seven stones at C. White's loss is too large to risk playing a ko. In the end, White loses by 1.5 points.

Diagram 2: If Black has a double wing position, a shimari with extensions in both directions, White must reduce Black's framework before it is too late. White 1 is sometimes played to that end. Black 2 is one of various responses. White's main objective should always be to make a light shape so it can form eyes quickly if necessary. White 3 and 5 are forcing moves and Black needs to defend with 6. White now lightly leans on Black's marked stone as it moves toward the center. Later, white A, which threatens a placement at B, is significant.

Diagram 3: In answer to white 7, Black might push with 8 before bending at 10. After 11, Black usually follows up with 12 to remove White's eye-space. White, however, may ignore this and keep developing in the center, e.g., with 13.

Diagram 4: (Black connects at the white marked stone.) If Black cuts with 1, the idea is to sacrifice the marked stone with 2 and 4. If Black connects at 5 (where the marked stone is), white 6 could take aim at A at a later stage.

Solution to last week's problem

Solution: The territories are not clear-cut, with contested stones at A and B and a huge endgame move at C. However, if we leave these problems for later and count the territories, Black (crosses) has 48 points while White (triangles) has 44.5 points (38 + 6.5 komi). Note that we have not counted the squares in the lower center. To stay in the game, White has to reduce Black's territory significantly, and the most likely place is around the lower center.

Reference: Doing some research on the position in Diagram 2, I found 31 games played between 1673 and 2004 with that pattern. However, only a few games employed a direct reducing technique. Just for fun, let's look at the 1673 game between Honinbo Dosaku and Yasui Santetsu. With black 31, the position has been established. White 32 reduces the expansion and threatens an invasion. This is carried out with 40. However, these stones quickly become a target for attack and Black easily wins the game by 12 points (in those days there was no komi compensation to White of 6.5 points).