I think things started going south for Iyama when he played that high move on the centre left (move 120, below), Park plonked a stone inside and Iyama ignored to bolster the connection of the wall above.
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[go]$$W Iyama (White) vs Park. moves 120-121
$$ +---------------------------------------+
$$ | . . . . . . . . . . X O . . . . . . . |
$$ | . . . . . . X X X . X O . O . O X . . |
$$ | . . . . . X O O O X X X O . O X . X . |
$$ | . . . X X O O X X O O O . . . X X O . |
$$ | . . . . . . . X O . . . O . O X O O . |
$$ | . . O . . O O X X X X X . . O X O X . |
$$ | . . . . . . . O O X O X . X X X O X . |
$$ | . . . . . . . . . O O . . . . . O . . |
$$ | . . . . . . . . . . . . . . . O . O . |
$$ | . . O , . . . . . , . X X X X X O O . |
$$ | . . . . 2 . . 1 . . O X O O O O X X . |
$$ | . . . . . . . . . X X O O O X X O X . |
$$ | . . . . . . . . . . . X O O O X . X . |
$$ | . . . . . . . . . . . X X O . . . . . |
$$ | . . . O . . . . . . . . . . O X X X . |
$$ | . . O , . O . . . X . . . . O , O O . |
$$ | . . . . X . X . . . . . X . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
- Click Here To Show Diagram Code
[go]$$W
$$ +---------------------------------------+
$$ | . . . . . . . . . . X O . . . . . . . |
$$ | . . . . . . X X X . X O . O . O X . . |
$$ | . . 2 . 8 X O O O X X X O . O X . X . |
$$ | . 4 1 X X O O X X O O O . . . X X O . |
$$ | . . 5 3 . 6 7 X O . . . O . O X O O . |
$$ | . . O . . O O X X X X X . . O X O X . |
$$ | . . . . . . . O O X O X . X X X O X . |
$$ | . . . . . . 9 . . O O . . . . . O . . |
$$ | . . . . . . . . . . . . . . . O . O . |
$$ | . . O , . . . . . , . X X X X X O O . |
$$ | . . 0 . X . . O . . O X O O O O X X . |
$$ | . . . . . . . . . X X O O O X X O X . |
$$ | . . . . . . . . . . . X O O O X . X . |
$$ | . . . . . . . . . . . X X O . . . . . |
$$ | . . . O . . . . . . . . . . O X X X . |
$$ | . . O , . O . . . X . . . . O , O O . |
$$ | . . . . X . X . . . . . X . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
Before that Michael Redmond thought the game was ok/nice for Iyama as he only needed about 30 points from that left side which looked very doable with sente, but then Iyama asked for a lot more and didn't try to kill black's invasion. So I have 2 questions about this sequence. First as Park (black) gave Iyama a few extra points for the right group to make sure his top right group was alive the threat of saving the cutting stone in the centre was a lot smaller, so why did Iyama play so high (one secondary aim of which was presumably threatening to save that stone, as well as helping a bit with the cuts in the wall above and surrounding the left) if it meant Park could easily invade. Secondly why tenuki the invasion and allow him to trash the side if you asked for more? No good answer? Would a more conservative move, such as one-point jump up from the 3-10 side stone (maybe too slow) or a large knight's move (2 spaces left of where he played, feels good to me) not be enough? Perhaps he feared being whittled down from all sides (black has some nice reduction from top left corner, cut the 3 stones in centre, corner slide in lower left) and wouldn't have enough? So he plays a big move asking for more, ignores the invasion to play the thick connection/yose at the the top left (forming an ugly empty triangle) and then defend the cut in the wall and aim to attack the invader on a large scale after it breaks the left side territory.
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[go]$$W Black (Park) trashes left (taking ko and threat x-y before 7 omitted)
$$ +---------------------------------------+
$$ | . . . . . . . . . . X O . . . . . . . |
$$ | . . . . . . X X X . X O . O . O X . . |
$$ | . . X . X X O O O X X X O . O X . X . |
$$ | . X O X X O O X X O O O . . . X X O . |
$$ | . . O O . X O X O . . . O . O X O O . |
$$ | . . O . . O O X X X X X . . O X O X . |
$$ | . . . . . . . O O X O X . X X X O X . |
$$ | . . . . . . O . . O O . . . . x O . . |
$$ | . . . . . . . . . . . . . . . O . O . |
$$ | . 7 O 3 . . . . . , . X X X X X O O y |
$$ | . 5 X 1 X . . O . . O X O O O O X X . |
$$ | . 6 . 2 . . . . . X X O O O X X O X . |
$$ | . . 4 . . 8 . . . . . X O O O X . X . |
$$ | . . . . . . . . . . . X X O . . . . . |
$$ | . . . O . . . . . . . . . . O X X X . |
$$ | . . O , . O . . . X . . . . O , O O . |
$$ | . . . . X . X . . . . . X . . O . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
As part of that attack he pressed the lower side, threatening to take a chunky bottom-left corner with 146 (3 below) if Park is generous and takes care of his invasion group for 147 instead of the most severe move he played of extending into corner (4 below). In that case I can appreciate his high move turns into solid territory above, solid territory below, and weakish black group in middle to tease which is more concrete profit than one big but thin and not-quite-solid large territory getting poked at from all sides (such poking also giving black a bit of additional territory). But with 147 Park challenged Iyama, "go on show me how you build a miai of saving the 2nd line cut or killing the left invasion". I think against his Japanese peers Iyama tends to manage a good result in this kind of complex fighting, but against Park he kind-of failed: yes he got a ko but it was messy and the bottom right wasn't alive yet and black had ko threats, so he got indigestion trying to eat those stones (and his group there had bad shape so chances to die thus heavy ko) and lost the top group in exchange.
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[go]$$W Park doesn't wimp out, fights severely with 4
$$ +---------------------------------------+
$$ | . . . . . . . . . . X O . . . . . . . |
$$ | . . . . . . X X X . X O . O . O X . . |
$$ | . . X . X X O O O X X X O . O X . X . |
$$ | . X O X X O O X X O O O . . . X X O . |
$$ | . . O O . X O X O . . . O . O X O O . |
$$ | . . O . . O O X X X X X . . O X O X . |
$$ | . . . . . . . O O X O X . X X X O X . |
$$ | . . . . . . O . . O O . . . . X O . . |
$$ | . . . . . . . . . . . . . . . O . O . |
$$ | . O O O . . . . . , . X X X X X O O O |
$$ | . O X O X . . O . . O X O O O O X X . |
$$ | . X . X . . . . . X X O O O X X O X . |
$$ | . . X . . X . . . . . X O O O X . X . |
$$ | . . . . . . . . . . . X X O . . . . . |
$$ | . . . O . . . . . . . . . . O X X X . |
$$ | . . O , 3 O . . . X . . . . O , O O . |
$$ | . . . 4 X 1 X . . . . . X . . O . . . |
$$ | . . . . 6 2 5 . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ +---------------------------------------+[/go]
What were the thoughts of Japanese/Chinese/Korean commentators about this critical stage of the game? I was pretty sure Park would win by move 143 (end of 3rd diagram).