BQM 209

    Keywords: Joseki, Ko, Shape, Question

34PointHighApproachOneSpaceLowPincer, kosumi, keima Question

[Diagram]
Diagram 8  

Rui Naiwei in Essential Joseki shows this variation on page 125. There she calls it a situational joseki. Ishida's Joseki Dictionary does not have W3 as an option.

Black presses at B4 seeking to control the balance of the whole board. But after White makes the diagonal play of W5, White has all the points. So lacking any special situation, Black can not use this diagram.

No other diagram is given for Black's response to W3.

tderz: it is important to think about protection vs. the cut a-b-c, e.g. with a move at d.

[Diagram]
Question Diagram  

What should White do if Black attaches on the inside at black+circle instead of B4 ?


dnerra: I think the usual continuation is the following (I am not quite sure here, though):

[Diagram]
Continuation  

The next black move is a nice shape tesuji that everybody who hasn't seen it should think about!

[Diagram]
shape tesuji  

AJP: dnerra evidently refers to the cathedral shape as shown here with B6.

unkx80: tderz, I observed that you changed White a to W7. Both are joseki.

[Diagram]
Joseki 1  

In this joseki, Black can play the large endgame move at B1 in sente (of course, "sente" here should take the temperature into account).

[Diagram]
Joseki 2  

In this joseki, Black can create a ko with B1 and B3, aiming at either a or b.



However, it seems that people nowadays prefer to play the first joseki.

tderz An honest question: are professionals really play Joseki 1, and more often than variant 2?

unkx80: I shall try to give a very quick answer before I go out for dinner.

A honest answer: I have not been studying professional games, so I don't know. One thing I always forget to do is to quantify my statements. When I say that "it seems that people nowadays prefer to play the first joseki", I base it on my perception from the very limited number of games I see and play.

[Diagram]
Joseki 1  

tderz Hello unkx80! Long time no see.

unkx80: Hi! =)

In Joseki variant 1, Black also has the ko aji B1-W2-B3! If the endgame exchange a-b has not taken place, the cutting points c, d exist.

[Diagram]
Joseki 1  

unkx80: Sure W4 fixes the problem, so Black does not get to atari where W4 is...

[Diagram]
Joseki 2  

tderz If, in Joseki 2, White connects safely at W4,
Black only could achieve something, if there was a Black stone at a. However, and here comes my conclusion as absolute 'non-Joseki-expert', Black wouldn't have found the time in sente to play there!
That's why I would prefer Joseki 2 over Joseki 1.

[Diagram]
Joseki 2  

unkx80: Don't tell me this is not a ko.

tderz: Oeps - overlooked it !

[Diagram]
Joseki 2 - sente, but rather slow  

tderz: If Black was moving to B1 here its sente (threatening the ko aji), but rather slow. W2 might be worth more.

unkx80: Here, I agree.


unkx80: I believe this also a joseki:

[Diagram]
Joseki  

W8 may be played at B9 for an extremely complicated fight which I am not too sure myself.

[Diagram]
Joseki  

AJP: All about joseki says the above diagram is not joseki and that W9 is bad for white after black extends to a rather than B10. They suggest this instead, in the context of white already having a position in the bottom left.

Velobici: Thank you very much unkx80. This is not too different from the game, there play went like this.

[Diagram]
Game continuation  

How should the Black handle the circled stone at this point? I felt that the result of the joseki favored White given Black's high stones and the right face a White position rather than a Black one, as might have happened if White had played W3 at a .

mAsterdam: Could you please explain? (And check the colors? I assume you meant to ask how White should handle the circled stone. I circled it as there was no circled stone. Please remove this comment after editing).

[Diagram]
Game continuation (1)  

Dieter: I think White may be happy to split Black this way.


BQM 209 last edited by Dieter on July 5, 2008 - 12:48
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