Akira's Top Right 48

  Difficulty: Expert   Keywords: MiddleGame
[Diagram]
Akira Toya's top right  

This is not the full board position, but a subset pieced together from different parts of chapters 48 and 49.

DaveSigaty: I think this is now the complete whole board position when Akira plays the marked stone. White cannot avoid being cut at one or the other of the points marked a and therefore cannot afford to cut at b. If he does cut, after Black c, White d, Black e, White captures two stones, Black recaptures, he can only make one eye in the corner. After long thought he abandons the idea of challenging Black to kill him and simply captures at f. The effect of this exchange, however, is that later White has to go back and live in the upper right in gote[1].

[Diagram]
If White cuts ... (5 at the marked point)  

Dave's comment illustrated:

[Diagram]
If White cuts at 'b' (continued)  

And White has only one eye and dies.

[Diagram]
White captures for life  

Thus White captures at f (marked stone) leading to this diagram. Note that White is alive! She either captures two black stones by playing b or she makes two eyes along the top by playing c.


[1] What do you mean by gote in your comment, Dave? (see last diagram above) --Arno

DaveSigaty: Sorry: actually I am completely wrong! Black's play in the upper right does force White to live. However, in the story Zama-sensei is able to do it in sente. Here is how.

First of all, Black finishes the original sequence by connecting at b (1 in the diagram below).

[Diagram]
Three birds with one stone!  

Next, White plays 2 which is a sacrifice stone that: allows White to play 6 in the next diagram below in sente in answer to 5, allows White to strengthen the white stones on the right (see the third diagram below), and prevents Black from making an eye in this area. It is a very impressive play.

Finally White plays 6 as the first of a series of forcing moves against the upper black group before living.

[Diagram]
White lives in sente  

White 4 ends up being sente against the top group. White uses his sente to play the hanging connection at 8 which also looks at the black group on the left.

[Diagram]
Black's forcing moves  

Black finishes his preparations by forcing in the upper right and exchanging 3 for 6 on the left side to strengthen things a bit there.

[Diagram]
Akira Toya's next big decision  

This is the point where Akira can protect the bottom and secure a lead but decides instead to play 1 out of fighting spirit (thinking of how Hikaru will be able to see the game report afterwards). Note how White plays 2 and 4 to strengthen his right-side stones before invading at 6.


Akira's Top Right 48 last edited by 172.29.20.40 on November 13, 2008 - 10:00
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