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BigQuestionMark

 

B Q M 25
  Difficulty: Advanced   Keywords: Question, Opening, Joseki

Hello. I'm posting this position for comment. There was what I thought to be an overplay in the joseki that I thought I punished fairly well, but at the end I had this odd feeling like one or both of us screwed up somewhere in the fight that ensued. I took in this game. Incidentally my opponent resigned after move 63. --BlueWyvern



[Diagram]
Diag.: The opening

Here's the whole board just for referance. Up to white 9 seems joseki but then white 10 feels like an overplay. The most important thing about the whole board in the next few diagrams is white 4, which makes the ladders in the lower right favorable for white.




[Diagram]
Diag.: The ensueing fight: part 1

I felt good, like I was controlling the fight from the beginning. The whole time I was really aiming at the cut at 'a'.



[Diagram]
Diag.: The ensueing fight: part 2

This seems like a favorable position to me. I got a fair chunk of the corner and a wall facing my lower left hoshi stone. She got a bit of territory and but her wall is facing my upper right hoshi stone. But I can't help the feeling that something in this fight has not gone quite right.



HolIgor: I think that white did too well in this position. They have what they wanted in this corner, i.e. a living group. The possibilities at the bottom is gone, though. But white's influence along the right side increased. What Black gained in addition to the wall is sente because extention at the bottom is not urgent now and can be very distant. Black can play large horse shimari in the left bottom corner, for example. Perhaps this makes the variation valid.


[Diagram]
Diag.: Joseki. After 10 black plays at the center of bottom side.

Let me explain how I understand this joseki at my level (IGS 5k*). White group in the corner is thick. There is no sente move against it. But at the same time W 10 is low, which means that a big territory on the left is unlikely (too many moves to spend and the opponent will not sleep at that time.

With a move like in the first diagram position still remains very slow, but the robustness is gone. There is aji in the position. So, it black does not hurry to punish right now white will alway feel the necessity to come back and protect.

The situation reminds me about the famous Sakata-Takagawa game in Honinbo challenger final in 1952.



DaveSigaty: I have to take a different view. I think the result in the corner was a disaster for White.

Black hit the weakness of the 2-space extension just right. The result with B building a wall facing his hoshi in the lower left is excellent. I doubt that capturing the two stones at the bottom are worth giving up sente for however. I think it is better to atari the two other white stones to complete a perfect wall and then play an approach move in the upper left. How does this look?


[Diagram]
Diag.: Something like this?

Note that the perfect wall is only possible because W made a mistake by playing the marked stone instead of 2 originally. If 2 had been played then W could ignore B 1 in order to play first on the left side. B could capture two stones but could not prevent W from connecting underneath. With the game continuation B 1 threatens 2 cutting W in half.

In the game B gets an extraordinary gift when W uses her sente (received when B captured two stones at the bottom) to capture one extra B stone while allowing B to perfect his wall. W should have played on the left side. However, B's huge wall is going to make it very difficult for W from here on.

It may be worth noting, that the wall was white's undoing in the end. She panicked, and tried to nullify it's influence resulting in a very pleasant result for black, and a resign after 63 moves for white. --BlueWyvern


BillSpight: Black has certainly come out well in the bottom right corner. Let's do a little tewari.


[Diagram]
Diag.: Tewari (i).

First, a couple of sente exchanges. W 3 elsewhere.
Black has lost 3 stones on the marked points.


[Diagram]
Diag.: Tewari (ii).

This shows the result of some of the pairings. The exchange of the circled stones is bad for White, and White's squared stone would be better off at a.

White's thinness can also be exploited on a larger scale. E. g.,


[Diagram]
Diag.: Larger scale attack.

B 5 attacks White's weakness on a larger scale, making a moyo in the process. A protective move at a, for instance, is just silly. W 6 is more enterprising, but Black still threatens the exchange, B 7 - B 9.



[Diagram]
Diag.: White has a better response?

So many people have already commented on this BQM. I think I'll just add another two cents. I think white 2 at a is an overplay, white can just play at 2 in this diagram and it's no big deal. --unkx80


[Diagram]
Diag.: Black seals White in?

DaveSigaty: What if B continues with 3 here? I think that B tends to find a way to shut W in. Since the upper right corner is a B stone, I think it is not so easy for W?

HolIgor: Yesterday, browsing the books in Kinokuniya again, I saw just this diagram. I can't read Japanese but I can look at diagrams :).

unkx80: OK, so my "no big deal" was wrong, but I think white is still better off playing at 2 in this diagram instead of 5. :-)


[Diagram]
Diag.: White reacts?

DaveSigaty: But on the other hand 3 may be an overplay, what happens if W answers 3 more aggressively with 4 and 6 here instead?


[Diagram]
Diag.: White pushes out into the center

If B captures the one stone, then W 4 threatens 5 and W 6 still threatens to descend at 7 in sente so B 7 seems forced. At this point W 8 attacks the 3 Black stones since B has not yet extended along the bottom from these stones. If B jumps, W has plays like 10 to protect the cutting point or may choose some other point like 'a' as an alternative. In all likelihood W will also have the chance to play first on the left side and is doing better than in the game?


[Diagram]
Diag.: White pushes B down

If B cuts at 1 here, W can either capture three B stones in exchange for the corner by playing 2 at 3 or else keep the corner as shown here. Being cut is not so painful since B has no recourse except to push along the second line on the right in order to live. W needs to do nothing except allow B to push her along; each stone adds to a very nice wall that will have a strong influence on the center at no cost.

Hmm... or is W dead in the corner after a B placement at 'a' unless she adds a stone?



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