Won endgame for white !?

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Nordlandia
Posts: 2821
Joined: Fri Sep 25, 2015 9:38 pm
Location: Sortland, Norway

Won endgame for white !?

Post by Nordlandia »

In SF selfplay (last developmental version against each other) with default contempt. White wins here.

[d]2b1k3/5p1p/1n1Rpp2/8/8/6P1/PPP4P/1K6 b - - 0 25

[pgn][Event "Corus"] [Site "Wijk aan Zee"] [Date "2002.01.21"] [Round "8"] [White "Timman, Jan H"] [Black "Gelfand, Boris"] [Result "1-0"] [ECO "B96"] [WhiteElo "2605"] [BlackElo "2703"] [Annotator "Tyomkin,D"] [SetUp "1"] [FEN "2b1k3/5p1p/1n1qpp2/8/8/6P1/PPP4P/1K1R4 w - - 0 25"] [PlyCount "11"] [EventDate "2002.01.12"] [EventType "tourn"] [EventRounds "13"] [EventCountry "NED"] [EventCategory "18"] [SourceTitle "CBM 087"] [Source "ChessBase"] [SourceDate "2002.03.21"] [SourceVersion "1"] [SourceVersionDate "2002.03.21"] [SourceQuality "1"] {[#]} 25. Rxd6 Nd5 26. c4 {All was forced till now...} Ke7 $4 {Black should move the knight instead, but I don't really know what black can oppose to white passed pawns over the queenside....} (26... Ne3 {This ending can be compared vs final position of the game Brodsky,M-Timoshchenko,G(see 19...Nxc4) - black is up a pawn here comparing vs that ending, but black has pair of bishops there and some counterplay as well. In both cases, white has chances to win thanx to 3 passed pawns over the queenside;} 27. c5 Nf1 (27... Ke7 28. b4 e5 29. a4 Nf1 30. a5 $18) 28. b4 Nxh2 29. b5 $16 {and white pawns are very dangerous;}) (26... Ne7 {was possible too, but it is a bit passive;} 27. b4 Nf5 28. Rd3 (28. Rb6 Ne3 29. b5 Nxc4 30. Rc6 Nd2+ 31. Kc1 Bd7 32. Rc7 $16) 28... Bb7 29. Kb2 e5 30. b5 $16 {and so on;}) 27. Rc6 $18 Bb7 28. cxd5 Bxc6 29. dxc6 Kd6 (29... f5 30. b4) 30. g4 $1 {Now black can advance his e-pawn maximum on e5 to keep it protected by f-pawn, but white easily wins there by moving his pawns to a5 and b5 and the king- to c5;} (30. b4 Kxc6 31. g4 $1 (31. a4 f5 $1 { and black would get his passed e-pawn on e4;})) ({The following lines show how white easily wins in that pawn ending:} 30. g4 Kxc6 31. Kc2 Kd5 32. Kd3 e5 33. b4 Kc6 (33... e4+ 34. Ke3 Ke5 35. a4 $18) 34. Kc4 Kb6 35. a4 Ka6 36. a5 Kb7 37. b5 Ka7 38. Kc5 Kb7 39. a6+ Ka7 40. Kc6 e4 41. b6+ Kxa6 42. b7 Ka7 43. Kc7 $18) 1-0 [/pgn]
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Nordlandia
Posts: 2821
Joined: Fri Sep 25, 2015 9:38 pm
Location: Sortland, Norway

Re: Won endgame for white !?

Post by Nordlandia »

I found this position by watching Kasparov's najdorf DVDs. White is much better but it's not clear if it's winning in the end.

[d]rn3b1r/2kn4/p7/1p1Q1Bpp/7q/8/PPP3PP/1K1RR3 b - - 0 22

[pgn][Event "https://lichess.org/pGSwa2se"] [Site "https://lichess.org/pGSwa2se"] [Date "2005.??.??"] [Round "?"] [White "Pol 12...Qe5 13.Bd3"] [Black "?"] [Result "*"] [ECO "B96"] [Annotator "lichess.org"] [PlyCount "43"] [EventDate "2005.??.??"] 1. e4 c5 2. Nf3 d6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 a6 6. Bg5 e6 7. f4 b5 $6 { (0.00 ? 0.60) Inaccuracy. Best move was Qb6.} (7... Qb6 8. Qd2 Qxb2 9. Rb1 Qa3 10. f5 Nc6 11. fxe6 fxe6 12. Nxc6) 8. e5 dxe5 9. fxe5 Qc7 10. Qe2 {B96 Sicilian Defense: Najdorf Variation, Polugaevsky Variation, Simagin Line} Nfd7 11. O-O-O Bb7 12. Qg4 Qxe5 $2 {(-0.03 ? 1.36) Mistake. Best move was Qb6.} ( 12... Qb6) 13. Bd3 h6 14. Bh4 g5 15. Nxe6 h5 16. Qh3 fxe6 17. Rhe1 Qf4+ 18. Kb1 Qxh4 $2 {(0.67 ? 1.85) Mistake. Best move was Be7.} (18... Be7) (18... Qg4) 19. Qxe6+ Kd8 20. Bf5 Kc7 21. Nd5+ $6 {(2.53 ? 1.67) Inaccuracy. Best move was Rxd7+.} (21. Rxd7+ Nxd7) 21... Bxd5 22. Qxd5 {Unterminated} * [/pgn]