It seems to me White can't lose this ending. It must have been time pressure.

southall:

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44.Bxg5?? (44.Bxe6 Kxe6 45.Bxg5 hxg4 46.Kxg4 d5 = and the opposite colored bishops gives Black the draw)

White King is in stalemate position after h2-h3 so White should try to block or give away pawns on the queenside. 49 h2-h3 is a possibility and if for example 49... a6-a5 then 50 c2-c3 b7-b6 51 b3-b4 Kmove 52 b4xa5 b6xa5 53 c3-c4 Now if Black maintains the stalemate , 54 c4-c5 d6xc5 55 d5-d6 draws. If Black releases the stalemate , White will play Kg3 followed by pushing the h-pawn.

cannibal: <paul1959>

I've looked at it for a while now, and I think 47. ... h4+ IS winning in all lines.

The clou is that black only makes a step to the fourth rank (a5 or b5) AFTER white does so. I.e., if 49.b4 (as in the game), then b5!, if 49.c4, then a5!, and if anything else (49.h3, Kh3, c3, or even a5), then b6!, and black just waits until white has to move b4 or c4.

One more thing I've been looking at: what if white decides NOT to go into stalemate with Kh4 and h3? Because in all the lines, white queens only one ply after black, so if there's any chance that he can avoid immediate mate somehow, he might be fine.

So, 49.Kh3 b6 50.b4 b5 51.a5 Kf2 52.c4

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(we want to play the suicide bomber c4 while the black king is on f2, as with the king on f3 the mate is rather trivial)

52. ...bxc4 53.b5 c3 54.b6 (bxa6 won't change anything) c2 55.b7 c1Q 56.b8Q

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and now at first I was a bit puzzled, because after e.g. Qf1+ Kh4, where's the mate? Fortunately, there's 56. ...Qc3+ 57.Kh4 Kg2!

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and white can neither give a check nor
prevent mate at h3.

Maybe Chucky didn't see through all this at the board, because if he did, I think it might have been worth trying. After all, Wang Yue blew a winning endgame in one move the round before, and it doesn't look totally impossible to play something like 56... Qe3+ in time trouble, suddenly finding yourself without continuation.

http://chessmind.powerblogs.com/fil...

http://www.chessbase.com/cbm/cbm129...

Peligroso Patzer:

The thought occurred to me recently that 49. a5 might have been better than Ivanchuk's 49. b4. I seem to recall that Kmoch in "Pawn Power" (which I read several eons ago) uses the term "quartgrip" to describe a winning formation that White would now get if he could also get in b4 and c4. This formation allows a breakthrough roughly similar to the well-known breakthrough with 1. b6 that is available in this position:

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.

Getting back to the Ivanchuk-Wang game, the 49. a5 idea does not work because White does not get time to get the b- and c-pawns to the fourth rank, and he ends up in a zugzwang much as in the game: 49.a5 b6 50.b4 b5 51.Kh3 Kf2 52.c3 Kf3 53.Kh4 Kg2 54.h3 Kf3 55.c4 bxc4 56.b5 c3 57.bxa6 c2 58.a7 c1=Q 59.a8=Q Qe1#.

Peligroso Patzer: For anyone who may be interested, here is an illustration (my own analysis; I have not checked Kmoch) how the "quartgrip" breakthrough works from the position below:

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1.b5 Kg3 2.c5 axb5 3.c6 bxc6 [3...b6 4.a6 (or 4.axb6 ) ] 4.a6

Peligroso Patzer: FWIW with regard to my comments above re: “quartgrip”, if one considers the position after 47. … h4+!! 48. Kxh4 Kf3!:

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… and if one now imagines that White could bring about the “quartgrip” formation in one move (instead on the three actually required), the following position (with Black to move):

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would indeed be winning for White regardless of whether Black tries the zugzwang idea that worked in the actual game: 1...Kf2 2.b5 Ke3 3.c5 Kd4 4.c6 b6 5.axb6 or tries to run his King immediately through the center to the Q-side: 1...Ke4 2.Kg3 Kd4 3.h4 Kxc4 4.h5 Kxd5 5.h6 c5 6.bxc5 dxc5 7.h7 c4 8.h8Q .

Kamalakanta,
44.♗e6 ♔e6 45.♗g5 looks pretty good to me, eg {45..hg4 46.Kg4) and White seems to have the advantage with the 2-1 pawn advantage on the Kingside.

SuperPatzer77

Just because Rybka has this opening loaded doesn't mean it's good.

Its hard to explain though to lower rated players who simply look superficually at the positions and see doubled pawns and suddenly think black is better.. its also about piece activity!! in fact the position is perfectly equal after both castle.

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