In the Samsung cup I rather liked the way Iyama dealt with another early attachment from Mateusz (for analysis of another in his game with Song Taekon see baduk1's review with Catalin Taranu 5p:
https://www.youtube.com/watch?v=_v_7l_8pG-M). After Mateusz (as black) played the slow but steady good shape move of 1 (something looser but fast-paced around L16 also possible, or the cheeky d18 maybe sente) Iyama split the top side and Mateusz attached on the left:
- Click Here To Show Diagram Code
[go]$$B Iyama Yuta 9p (white) vs Mateusz Surma 1p
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There's a rather similar move when white wedges the side of a mini-Chinese opening. I think the plan is if white plays the natural looking hane on top then white ought to defend the cut and black gets to play on both sides. On a simple level black's attachment looks a bit weird, attaching to a weak (or at least not-strong) stone thus making it (locally) stronger, but it does end up unable to make a nice extension and has a somewhat heavy feeling.
- Click Here To Show Diagram Code
[go]$$W Mateusz's plan?
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So Iyama played hane underneath and Mateusz played counter hane (extend back is a bit soft shape), offering a trade of white can capture that stone on the 2nd line but then he captures the other in a ladder to nicely build the right side (and the white ponnuki is still cramped on the top side). So Iyama tenukid and attached in the corner and it turned into a shape like the small avalanche but with black extending instead of hane for 10:
- Click Here To Show Diagram Code
[go]$$W
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$$ | . . . . . . . . . X O . . . . . 7 . . |
$$ | . . O O X . . . . . X O . 0 4 2 1 . . |
$$ | . . O X . X . . . , . . . . 9 3 X 6 . |
$$ | . . O X . . . . . . . . . . . . 5 8 . |
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Mateusz connected on the top side making 3rd line territory, nothing too spectacular, and white's 2 corner stones still had troublesome aji.
- Click Here To Show Diagram Code
[go]$$W
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$$ | . . . . . . . . . X O 6 8 . . . O . . |
$$ | . . O O X . . . . 2 X O 4 X X X O . . |
$$ | . . O X . X . . . , 1 7 5 3 O O X X . |
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$$ | . . . X . . . . . . . . . . . . 9 0 . |
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So white could hane on the 2nd line after extending twice, and Mateusz, after cutting once to give white bad aji, needed to come back to complete the corner capture. Iyama then capture the cutting stone in a ladder. Black was pushed down to the 2nd line on the right side, which looks pretty succcessful for white to me. Black does have the aji of a ladder breaker, but in fact when he pulled the stone out quite some time later Iyama could just sacrifice it on a small scale with the squeeze at
b (and even better his defence of the cutting point with
i was a double purpose move in attacking a black group in the lower right). I wonder if this was one of those situations where black should have pulled out the ladder stone once earlier as a probe: it's rather lossy if white does then capture 2 stones with a tortoise-shell rather than ponnuki shape, but the squeeze sucked too.
- Click Here To Show Diagram Code
[go]$$W
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$$ | . . . . . . . . . X O X X . . . O 6 . |
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$$ | . . . X . . . . . . . . . . . . O X . |
$$ | . . O . . . . . . . . . . . . . 1 2 . |
$$ | . . . . . . . . . . . . . . . 7 4 3 h |
$$ | . . . . . . . . . . . . . . . g a 5 . |
$$ | . . . , . . . . . , . . . . . b c e . |
$$ | . . . . . . . . . . . . . . . . d f . |
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