|Jul-08-12|| ||Shams: An endgame tragicomedy for Topalov.|
|Jul-08-12|| ||Peligroso Patzer: When I first looked at this endgame, I thought that Topalov was lost after <68.
Kh2><?>. (Better would have been <68.
Nc7>.) After that, it seemed that White was able (by force) to mop up the Black pawns and then run over to promote the a-pawn before Black could get his King back towards the a8-corner in sufficient time to stop the passed a-pawn..|
It turns out (based on checking the tablebase at: http://www.shredderchess.com/online...) that <75.
Kh2><?> was actually the losing move. (Either <75.
Kh4> [making for the a8-corner more quickly than in the game] or <75.
Na8> [at least not moving the King away from the a8-corner, as the text, <75.
Kh2>, does] would have drawn. [Note: In the <75.
Na8> line, as play proceeds, the tactics of the drawing line get very tricky. In the <75.
Kh4> line, although Black does not actually win the White Knight, that piece cannot stray too far from its duties restraining the passed Black g-pawn, so even though it remains on the board, the White Knight cannot help with promoting the a-pawn.]
One final observation: Since a rook-pawn on the 7th rank is the only type of pawn that a Knight cannot blockade/restrain (when the pawn is supported by its King, and the defending King is too far away to contribute to holding back the pawn), <65.
Nc7> (allowing <66. a7>) was also a significant inaccuracy on Topalovs part (although not actually losing). [For a good example of an ending in which the superior strength of a rook-pawn on the 7th rank (in Knight endings) proves decisive, see: Kramnik vs Shirov, 2007.
|Jul-08-12|| ||Eyal: <Since a rook-pawn on the 7th rank is the only type of pawn that a Knight cannot blockade/restrain (when the pawn is supported by its King, and the defending King is too far away to contribute to holding back the pawn), <65...Nc7> (allowing <66. a7>) was also a significant inaccuracy [...] (although not actually losing).>|
I believe Carlsen vs Mamedyarov, 2012 is another relevant example from this very tournament - though it's a somewhat different case, of 2 pawns vs. knight:
click for larger view
here, 55...Nc7?? - allowing 56.a7 - instead of 55...Kc5/d5 <was> the losing mistake. A crucial factor is that with the pawn kept on the 6th rank the strategy of pulling the black king to the K-side and then rushing to the Q-side to attack the black knight doesn't work, e.g. 55...Kd5! 56.h4 Ke6 57.Kg5 Kf7 58.h5 Kg7 59.Kf5 Kh6 60.Ke5 Kxh5 61.Kd5 Na7 62.Kc5 Kg5 63.Kb6 Nc8+ 64.Kb7 Nd6+ 65.Kc6 Nc8 66.Kc7 Na7 67.Kb7 Nb5 68.Kb6 Nd6.
|Jul-10-12|| ||dumbgai: Reminds me of my own game last week: up a clear passed pawn and managed to LOSE.|
|Sep-21-12|| ||Fusilli: Unbelievable...|
|Sep-21-12|| ||dehanne: Topalov really went off the deep end.|