This is a game by Mori Hironobu from the 47th Amateur Honinbo tournament, the 2001 preliminaries. Black was 19 year-old Takizawa Yuta of Waseda University, runner-up in the All-Japan Students Honinbo. Mori was then 27. he had already been runner-up in the 45th Amateur Honinbo. He won this game without counting. The comments are by Pieter Mioch.
1 ~ 21
Black 13: Mori had not seen this move before but he did choose the strongest possible continuation, pushing through with 14 and 16 leading up to the cut at 18.
22 ~ 46
Mori had read out that after White 42 he could either start a ladder from one point above 40 or above 27, as shown in Diagram 1. What he didn't know was that Takizawa had prepared this sequence in advance and knew the perfect counter to White 42, the double ladder breaker at 43!
Diagram 1: White captures Black in a ladder.
Black 7 connects at 2
According to Kono Rin 7-dan at the time, however, Takizawa's carefully worked out plan was not that impressive. Let's have a look at Diagram 2.
Diagram 2: After the forcing move 1, White can neatly seal Black in by playing 3 and 5 in sente. Although Black has gained profit, White is thick and has the invasion at A to look forward to. According to Kono if this were to appear on the board it cannot be said that Black's position would be superior to White's.
47 ~ 77
The reason why Mori handed me this game record (said Pieter) when I asked for one of his games to put up with the article is this position and the move which comes right after it. White is very thin at the top. Where would you play next, and why?
78 ~ 100
White 78! Now, how many of you had figured that for White playing at 82 might now be a good idea to defend the two cutting points? Mori's reason for playing 78 instead was simple. He actually wanted Takizawa to push through and cut with 79 and 81. And Black did exactly that. In retrospect, however, Black should not have cut and started a new fight. For Black playing defensively and switching to 89 at the earliest opportunity is the way to go. Once Black can get rid of the bad aji in the lower right corner stones, he has a solid lead.
Now Mori got the chance to play the move he had prepared on the spot (when he played 78): the nice attachment at 88! Look at Diagram 3 to find out what happens if Black resists.
Diagram 3: Black 1 seems only natural but now the ladder from White 2 works perfectly and Black will have a very difficult game (unless he manages to capture the White stones at the top - that, however, was not a realistic idea according to Takizawa).
101 ~ 129
White now has enough to cruise to victory. When playing 106, however, he almost makes it an open game again. After 119 Black has secured a lot of extra territory in the upper right corner and White's group at the right side is not completely safe yet.
130 ~ 169
A big furikawari is being set up.
170 ~ 214 (moves after 214 omitted)
A huge furikawari (trade) is taking place late in the game, it does not influence the outcome, though. Mori manages successfully to cling on to the lead and secure a win.
Sgf version: 