Following Iyama Yuta (no world ranking discussions)
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macelee
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Re: Following Iyama Yuta (no world ranking discussions)
My counting is that Ichiriki Ryo has 9 win and 23 loss against Iyama. It's good that he can finally win some winnable games.
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Uberdude
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Re: Following Iyama Yuta (no world ranking discussions)
Iyama's slumming it back in the Meijin league today, first game against youngster Mutsuura Yuta 7d.
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Uberdude
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Re: Following Iyama Yuta (no world ranking discussions)
Yamashita beat Iyama in the 4th Tengen game by 2.5 after a nice kill, so Iyama has 2 deciding 5th games coming up: Ichirki in the Oza on 13th and Yamashita for Tengen on the 18th December. So could only have 2 3 of the big 7 titles after that.
Edit:
Kyo Kagen took the Gosei
Cho U took the Meijin
decider vs Ichiriki in Oza
decider vs Yamashita in Tengen
Kisei final vs Yamashita starts in Jan
Honinbo league in progress (Hane and Ichiriki lead 3-0 currently)
Judan at semifinals for challenger (Murakawa, Onishi, Yamashita, Takao)
Edit:
Kyo Kagen took the Gosei
Cho U took the Meijin
decider vs Ichiriki in Oza
decider vs Yamashita in Tengen
Kisei final vs Yamashita starts in Jan
Honinbo league in progress (Hane and Ichiriki lead 3-0 currently)
Judan at semifinals for challenger (Murakawa, Onishi, Yamashita, Takao)
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Uberdude
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Re: Following Iyama Yuta (no world ranking discussions)
Iyama beat Ichiriki by resignation in the deciding 5th game to keep his Oza title. It was a pretty convincing win, FineArt had Iyama around 90% for most of the game (move 67 to resign over 100 moves later).
- Seems like Ichiriki got into a difficult situation early with his q4 AI-style attachment making a heavy group, FineArt wants to tenuki and LZ prefers simple p4 and it becomes like a large avalanche but with white extend not hane.
- Iyama could (FA suggests) have just answered p7 at q7 and said thanks for the bad exchange, allowing black m8 but I suppose he had the sharp shape attack of o6 and q2 squeeze combo planned. My LZ misjudged the power of that at low playouts.
- Black having to defend at n5 is painful, bots suggest m3 cut first: if white has to answer at o3 that's nice (because it's a probe now and later white can easily sacrifice the 3 stones) but actually it seems white can m2 and the squeeze is still good for white so black would be stuffed.
- Black settling on the outside not bad though (FA 45%)
- But why not black hane at f5? It seems like Ichiriki tricked himself with the j6 k4 attachments as they resulted in getting the m3 cut but that only got 3 now-small stones whilst his corner cried.
- c2 passive, keep fighting on outside and there's not a clean kill and black can make other things more important first.
- By move 70 it's kinda game over, black is just pulling out some heavy stones with white safe on both sides.
- There's some more fighting but it all seems within Iyama's control as he settles both groups at top right, even making nice use of q8 with a little sacrifice.
- Black resigns at 186, either his big heavy group from before gets cut and dies, or to save it white saves his top left, plus the black upper middle doesn't have 2 clear eyes yet either.
- Seems like Ichiriki got into a difficult situation early with his q4 AI-style attachment making a heavy group, FineArt wants to tenuki and LZ prefers simple p4 and it becomes like a large avalanche but with white extend not hane.
- Iyama could (FA suggests) have just answered p7 at q7 and said thanks for the bad exchange, allowing black m8 but I suppose he had the sharp shape attack of o6 and q2 squeeze combo planned. My LZ misjudged the power of that at low playouts.
- Black having to defend at n5 is painful, bots suggest m3 cut first: if white has to answer at o3 that's nice (because it's a probe now and later white can easily sacrifice the 3 stones) but actually it seems white can m2 and the squeeze is still good for white so black would be stuffed.
- Black settling on the outside not bad though (FA 45%)
- But why not black hane at f5? It seems like Ichiriki tricked himself with the j6 k4 attachments as they resulted in getting the m3 cut but that only got 3 now-small stones whilst his corner cried.
- c2 passive, keep fighting on outside and there's not a clean kill and black can make other things more important first.
- By move 70 it's kinda game over, black is just pulling out some heavy stones with white safe on both sides.
- There's some more fighting but it all seems within Iyama's control as he settles both groups at top right, even making nice use of q8 with a little sacrifice.
- Black resigns at 186, either his big heavy group from before gets cut and dies, or to save it white saves his top left, plus the black upper middle doesn't have 2 clear eyes yet either.
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Uberdude
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Re: Following Iyama Yuta (no world ranking discussions)
By defending the Tengen title Iyama's now won 43 editions of the big 7 Japanese titles, surpassing Cho Chikun's record of 42. Cho won 10 Honinbo titles in a row, Iyama's currently on 7, can he match/beat that?
From https://twitter.com/asahi_photo/status/ ... 3219690496
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Uberdude
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Re: Following Iyama Yuta (no world ranking discussions)
Kisei game 1 vs Yamashita is live now
https://share.yikeweiqi.com/golive/detail/id/14760
A fun attachment (seen in joseki) to end the first day.
Update: Iyama won by resign. LZ thought he was doing well with the top side fighting but then lived too passively and Yamashita took the lead, but then Iyama reversed it with his lower side invasion (Yamashita played too much dame, presumably hoping for a large scale attack but Iyama settled easily).
https://share.yikeweiqi.com/golive/detail/id/14760
A fun attachment (seen in joseki) to end the first day.
Update: Iyama won by resign. LZ thought he was doing well with the top side fighting but then lived too passively and Yamashita took the lead, but then Iyama reversed it with his lower side invasion (Yamashita played too much dame, presumably hoping for a large scale attack but Iyama settled easily).
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Uberdude
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Re: Following Iyama Yuta (no world ranking discussions)
Kisei game 2 so far to move 54. Interesting fighting and exchange from Yamashita's (white) resistance at e14. I thought it was pretty nice for him to get that huge left side with good aji particularly as he got sente to close at c6 so it's going to be difficult for black to invade/reduce there. LZ agrees and says it was great for white and Iyama shouldn't have so easily given up on d13 and the e12 stones even though he got super thick (or overconentrated and forced?) on the top side. I wonder if there's a nice tewari. Anyway, Yamashita has to settle his top side group now so still plenty of chance to screw up his 86% lead (Elfv1 98%) and for Iyama to show his strength, I added an LZ example of settling, nicely using the aji of the dead white stones.
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- Iyama Yamashita Kisei 2019 g2.sgf
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Uberdude
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Re: Following Iyama Yuta (no world ranking discussions)
Yamashita kept on fighting well, here's the game to the end. LZ approved of his r11 q6 combo, though slightly preferred to just spend a move on the top group at k18. The o11 q9 combo is a new joseki from these AI corner attachments and worked particularly well as part of his sabaki. I can't understand Iyama's q13 defence, what was he scared of? (Maybe trying to play in a less forcing way to give white more opportunities to mess up, goading him into overplay?) LZ thinks it halves his winrate (10% to 4%). But then Yamashita didn't make the simple solid connection at o13 (LZ's #1) but s10 to save the r7 cutting stones because he wanted to pull out his o7 to attack n7. That seemed unnecessarily risky to me and could give Iyama some chances to reverse the game but Yamashita handled the fight well and got an easy ko with sequence to m12 (an LZ blindspot, so LZ's preference to sacrifice some stones to solidly save the rest were based on thinking this fighting variation wasn't as good for white as it really was). Iyama resigned soon after when white sealed off his left side after Iyama connected the right side ko. A very nice game from Yamashita.
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- Kisei final game 2.sgf
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- Iyama Yamashita Kisei 2019 g2.sgf
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Uberdude
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Re: Following Iyama Yuta (no world ranking discussions)
Kisei game 3, can you find Iyama's 42% mistake and Yamashita's 44% return of the favour; Iyama (white) won in the end. LZ's suggested move is the one I expected watching the game and its analysis appears sound to me. Is it missing something, or did the players really make such a big mistake?
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- Iyama vs Yamashita Kisei 2019 game 3.sgf
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Uberdude
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Re: Following Iyama Yuta (no world ranking discussions)
Iyama has got off to a bad start in the Meijin league, so what may have been assumed as a foregone conclusion that he would top the league to challenge Cho U to regain his title may not be so certain. He started off with a win against Mutsuura Yuta 7d, but then lost to Suzuki Shinji 7d (who? you may ask) by half a point. And just today he lost to prodigal youngster Shibano Toramaru 7d by 1.5 so he's 1-2 so far, with 5 games left.
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Uberdude
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Re: Following Iyama Yuta (no world ranking discussions)
Here is the position after move 189. White's stick on row 8 has just finished hassling the black group above and the fight resumed at the bottom left corner. White can push and cut with a-c to capture the cutting stones (each has 3 liberties but black needs to defend the g5 stones so white goes first), but would also like to kill the corner too if possible. LZ 203 says white is at 84%. First, what if white simply goes for the cut and capture. If white 7 takes a liberty black can connect under in sente and gets to play an important move like r4 next. White ends at 22%.mhlepore wrote:You can't leave us hanging... What was the 42% mistake?
Instead of 7 white can put in the sente hane in the corner to prevent black's connection, but then black can make a comb group to live in the corner. White 40%.
Starting with the hane in the corner seems pretty natural to me (and is the correct move says LZ), those white stones are weaker than the wall above so it makes sense to play from that direction, and that hane can often gain you a liberty in a semeai. If black extends with 2 (not best) to make the possibility of a comb group life, white captures a stone with b5 (not best), black ataris with b4 (not best) then white has, in sente, reduced the corner to one eye and got the b1 hane. White up to 96% with black's cooperation. Note that 4 above is a mistake, it's better at 6, then white pushes and captures a stone and black gets to defend at f5 and the corner will be a ko. So 3 was also a mistake, it should be at the vital point of 6 too and white is then successful in turning the black corner into 1 eye in sente as before and f5 push and cut. So 2 was also a mistake, see later.
So next white pushes and cuts, and that handy b1 hane means black can no longer connect under in sente, only gote. A big difference. So if white hanes in the corner it's better for black to make the hanging connection. Now if white wants to reduce it to 1 eye (best) its gote instead of sente like it was with the descent. If black f5 white can tenuki as the corner is still a ko, so black probably plays in lower right. If instead of 3 above white pushes and cuts then black can sort-of live in the corner next (thought lower right may be bigger). 13 doesn't work because black can connect under with 16, and although there is a ko at a2 black winning it is atari so nigh on impossible for white to fight. So that's what white should do. But Iyama didn't hane in the corner but just captured the outside stone directly. LZ says this lost 42%, white down from 85 to 43%. But this is only if black descends at the vital point in the corner. White can then push and cut as before, but black connects underneath in sente and can move to the lower right. Admittedly black doesn't actually connect to an alive group as he can't get e3 too and LZ might throw away the whole group later in a trade for p4 group later... LZ gives black 52% now. But instead Yamashite played the a4 decent to prevent that atari, -47% says LZ, but then Iyama got to hane in the corner and it ends up sort of like if white played the hane first. If black plays a2 white can just push and cut and black only has the pathetic gote connection like before, so black defended f5 and the corner will be a ko, but white gets sente and is at 91%.
So is there something wrong in this analysis, a move LZ overlooked or dubious judgement? I don't think Iyama could have been scared of the ko in LZ's correct answer, seeing as he went for a ko in the game anyway.
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mhlepore
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Re: Following Iyama Yuta (no world ranking discussions)
Ah very cool - thanks Uberdude. There was a messy fight right from the start so I really had no idea of the goof was earlier or not.