Author: Uri Blass
Date: 20:11:38 07/31/04
Go up one level in this thread
On July 31, 2004 at 17:48:17, Mark Young wrote: >On July 31, 2004 at 17:14:49, James T. Walker wrote: > >>On July 31, 2004 at 10:21:28, Vincent Lejeune wrote: >> >>>On July 31, 2004 at 07:24:15, Mark Young wrote: >>> >>>>[d]3q3r/4b1k1/4P1p1/rpp2p1p/1nn2Q2/5N1P/P4PP1/RBB1R1K1 w >>>>Another GM sac refuted by computers? >>>> >>>>This position is from... >>>> >>>>GM Fischer - GM Leonid Stein >>>>Interzonal, Sousse 1967 >>>> >>>>GM Fischer played the (so called) winning move Bxf5! Annotators claim GM Fischer >>>>wins easily after Bxf5! gxf5 Qg3+ Kh7 Ng5+ Bxg5 Bxg5 Qe8(or Qd3). >>>> >>>>For this reason GM Stein played Qf8? and lost...but Bxf5 gxf5! seems to more >>>>then hold the position. Do any computers or humans disagree. >>>> >>>>Example line. >>>>Bxf5 gxf5! Qg3+ Kh7 Ng5+ Bxg5 Bxg5 Ra3!. >>> >>>after the forced line Bxf5 gxf5! Qg3+ Kh7 Ng5+ Bxg5 Bxg5 Ra3! >>> >>>[D]3q3r/7k/4P3/1pp2pBp/1nn5/r5QP/P4PP1/R3R1K1 w - - 0 1 >>>Analysis by Shredder 8; amd@3000+ ; 2 best lines after 10 min >>> >>>1. ³ (-0.55): 5.Df4 Df8 6.Tad1 >>>2. -+ (-1.76): 5.Dh4 De8 6.Ted1 Cd3 7.Fc1 Cxc1 8.Taxc1 Dxe6 9.Te1 Dc6 10.Dxh5+ >>>Dh6 11.Dxf5+ Dg6 12.Dxc5 Dxg2+ 13.Rxg2 Tg3+ 14.fxg3 Ce3+ 15.Txe3 >>> >>>Fischer blundered and his opponent followed him ! ;o) >> >>I don't agree. First of all the line you give as "forced" is not forced. I >>guess it was provided by the "experts" who said it was a great sac. I doubt >>that computers can prove that Bxf5 is either good or bad at this time. There is >>still a lot of chess to be played after gxf5. Even gxf5 may not be the best >>response. >>Jim > >I have looked the position for sometime. What is clear is gxf5 is the only good >response. Everything else I have looked at proves the Bxf5 right, except gxf5. >The one move the GM annotators say loses for sure. I can not find a win for >white after Bxf5 gxf5. There is probably a win for white after Bxf5 gxf5 Try Qg3+ Kh7 Bg5 With the following analysis after Bg5 [Event "40'/40"] [Site "MyTown"] [Date "????.??.??"] [Round "?"] [White "New game"] [Black "?"] [Result "*"] [SetUp "1"] [FEN "3q3r/4b2k/4P3/rpp2pBp/1nn5/5NQP/P4PP1/R3R1K1 b - - 0 1"] [PlyCount "10"] [TimeControl "40/2400:0"] 1... Rg8 (1... Ra6 2. Rad1 Bd6 3. Rxd6 Qxd6 4. Qh4) (1... Ra7 2. Bxe7 Qxe7 3. Ng5+ Kh6 (3... Kg6 4. Nf7+ Kh7) (3... Kg7 4. Nf7+ Kh7) (3... Kg8 4. Nf7+ Kh7) 4. Nf7+ Kh7 5. Qf3 Kg7 6. Nxh8 Kxh8 7. Qxh5+ Kg8 8. Rad1) (1... Ra3 2. Qh4) ( 1... Nd6 2. Rad1) (1... Qg8 2. Rad1) 2. Rad1 Nd3 (2... Nd5 3. Qh4 Rxg5 4. Nxg5+ Kg6 5. g4) (2... Nd6 3. Bxe7 Qxe7 4. Qxd6 Qxd6 5. Rxd6 Re8 6. Re5) (2... Qe8 3. Rd7) 3. Qh4 Rxg5 4. Nxg5+ Kg6 5. g4 fxg4 6. hxg4 * I gave Yace to learn from this tree and the result is a clear advantage for white New game [D]3q3r/4b2k/4P3/rpp2pBp/1nn5/5NQP/P4PP1/R3R1K1 b - - 0 1 Analysis by Yace 0.99.87: 1...Bxg5 = (-0.16) Depth: 1 00:00:00 1...Bxg5 = (-0.16) Depth: 1 00:00:00 1...Bxg5 2.Nxg5+ Kg7 = (-0.16) Depth: 2 00:00:00 1...Bxg5 2.Nxg5+ Kg7 = (-0.16) Depth: 2 00:00:00 1...Bxg5 2.Nxg5+ Kg7 3.Nf7+ Qg5 4.Nxg5 Nxa2 +- (3.62) Depth: 3 00:00:00 1...Bxg5 2.Nxg5+ Kg7 3.Nf7+ Kh7 4.Nxd8 +- (4.18) Depth: 3 00:00:00 1...Rxa2 2.Bxe7 +- (4.17) Depth: 3 00:00:00 1...Rxa2 2.Bxe7 Qxe7 3.Qh4 = (-0.16) Depth: 3 00:00:00 1...Rxa2 2.Bxe7 Qxe7 3.Qh4 = (-0.16) Depth: 3 00:00:00 1...Rxa2 2.Bxe7 Qxe7 3.Ng5+ Kg8 4.Nf7+ Kh7 5.Ng5+ Kg8 6.Nf7+ Kh7 7.Ng5+ = (0.00) Depth: 4 00:00:00 1...Re8 2.Bxe7 Rxe7 3.Rad1 = (-0.01) Depth: 4 00:00:00 1...Re8 2.Rad1 Qc8 3.Rd8 = (-0.16) Depth: 4 00:00:00 1...Re8 2.Rad1 Qc8 3.Rd8 = (-0.16) Depth: 4 00:00:00 1...Re8 2.Rad1 Qc8 3.Rd8 = (-0.16) Depth: 5 00:00:00 1...Re8 2.Rad1 Qc8 3.Rd8 = (-0.16) Depth: 5 00:00:00 1...Re8 2.Rad1 Qc8 3.Bxe7 Rxe7 4.Rd8 = (-0.16) Depth: 6/19 00:00:00 31kN 1...Re8 2.Rad1 Qc8 3.Bxe7 Rxe7 4.Rd8 = (-0.16) Depth: 6/20 00:00:00 31kN 1...Re8 2.Rad1 Qc8 3.Bxe7 Rxe7 4.Ng5+ Kh6 5.Nf7+ Rxf7 6.Kh2 = (-0.16) Depth: 7/22 00:00:01 122kN 1...Re8 2.Rad1 Qc8 3.Bxe7 Rxe7 4.Ng5+ Kh6 5.Nf7+ Rxf7 6.Kh2 = (-0.16) Depth: 7/24 00:00:01 122kN 1...Re8 2.Rad1 Qc8 3.Rd7 Nc6 4.Qh4 Rxa2 5.Bxe7 = (0.21) Depth: 8/24 00:00:01 614kN 1...Ra8 2.Bxe7 Qxe7 3.Qf4 = (0.20) Depth: 8/28 00:00:01 2237kN 1...Ra8 2.Bxe7 Qxe7 3.Ng5+ Kh6 4.Nf7+ Kh7 5.Qf3 Kg6 6.Qg3+ Kh7 = (0.00) Depth: 8/28 00:00:02 2511kN 1...Ra8 2.Bxe7 Qxe7 3.Ng5+ Kh6 4.Nf7+ Kh7 5.Qf3 Kg6 6.Qg3+ Kh7 = (0.00) Depth: 8/29 00:00:03 3757kN 1...Ra8 2.Qh4 Re8 3.Qxh5+ Kg8 4.Qf7+ Kh8 5.Nh4 Ne5 6.Rxe5 Rf8 7.Qxf8+ Kh7 ² (0.40) Depth: 9/30 00:00:04 4725kN 1...Ra8 2.Qh4 Qe8 3.Bxe7 Nc2 4.Qf6 Nxa1 5.Rxa1 Rc8 6.Qxf5+ Qg6 7.Ng5+ Kg7 8.Qd5 ± (1.21) Depth: 9/30 00:00:06 7645kN 1...Re8 2.Rad1 Qc8 3.Rd7 Nc6 4.Qh4 Kg8 5.Qxh5 ± (1.20) Depth: 9/30 00:00:07 8475kN 1...Re8 2.Red1 Nd5 3.Bxe7 Rxe7 4.Ng5+ Kh6 5.Nf7+ Rxf7 6.exf7 Ncb6 7.Qe5 f4 8.Qxf4+ Nxf4 9.Rxd8 ² (0.49) Depth: 9/30 00:00:08 10338kN 1...Nc2 2.Bxe7 Qxe7 3.Ng5+ Kg7 4.Nf7+ Kh7 5.Nxh8 Nxe1 6.Rxe1 Kxh8 7.Qh4 ² (0.48) Depth: 9/30 00:00:14 16741kN 1...Nc2 2.Qh4 Qe8 3.Bxe7 Nxe1 4.Rxe1 Rg8 5.Ng5+ Kg6 6.Bxc5 Rxa2 ² (0.29) Depth: 9/30 00:00:15 18586kN 1...Nc2 2.Qh4 Qe8 3.Bxe7 Nxe1 4.Rxe1 Rg8 5.Ng5+ Kg6 6.Bxc5 Rxa2 ² (0.29) Depth: 9/30 00:00:16 19497kN 1...Nc2 2.Qh4 Qe8 3.Bxe7 Nxe1 4.Rxe1 Rg8 5.Ng5+ Kh6 6.Nf7+ Kg7 7.Bxc5 Ra3 ² (0.69) Depth: 10/35 00:00:18 21184kN 1...Nc2 2.Qh4 Qe8 3.Bxe7 Nxe1 4.Rxe1 ² (0.69) Depth: 10/35 00:00:22 27106kN 1...Nc2 2.Qh4 Qe8 3.Bxe7 Nxe1 4.Rxe1 ² (0.69) Depth: 10/35 00:00:39 45316kN 1...Nc2 2.Qh4 Qe8 3.Bxe7 Nxe1 4.Rxe1 Rxa2 5.Bxc5 Rg8 6.Ng5+ Kh6 7.Nf7+ Qxf7 8.exf7 Kg7 ± (1.09) Depth: 11/36 00:00:43 49738kN 1...Nc2 2.Qh4 Qe8 3.Bxe7 Qg6 4.Bxc5 Re8 5.Ng5+ Kh6 6.Qxc4 bxc4 7.Bb4 ± (1.09) Depth: 11/40 00:00:58 70088kN 1...Qf8 2.Bxe7 Qxe7 3.Ng5+ Kg8 4.Nf7+ Kh7 5.Qf4 Kg7 6.Nxh8 Kxh8 7.Qxc4 ± (1.08) Depth: 11/40 00:02:18 157194kN 1...Qf8 2.Bxe7 Qxe7 3.Ng5+ Kg7 4.Nf7+ Kh7 5.Qf4 Kg7 6.Rad1 Raa8 7.Qg3+ Qg5 8.Nxg5 Nxa2 ± (1.08) Depth: 11/40 00:02:19 157606kN 1...Qf8 2.Bxe7 Qxe7 3.Ng5+ Kg7 4.Nf7+ Kh7 5.Qf4 Kg7 6.Rad1 Raa8 7.Qg3+ Qg5 8.Nxg5 Nxa2 ± (1.08) Depth: 11/40 00:02:28 167066kN 1...Qf8 2.Bxe7 Qxe7 3.Ng5+ Kg7 4.Nf7+ Kh7 5.Qf4 Kg8 6.Qb8+ Qf8 7.Qg3+ Qg7 8.Qxg7+ Kxg7 9.Nxh8 Kxh8 10.e7 Nd6 11.e8Q+ Nxe8 12.Rxe8+ Kg7 13.a3 ± (1.19) Depth: 12/40 00:03:29 233937kN 1...Qf8 2.Bxe7 Qxe7 3.Ng5+ Kg7 4.Nf7+ Kh7 5.Qf4 Kg8 6.Qb8+ Qf8 7.Qg3+ Qg7 8.Qxg7+ Kxg7 9.Nxh8 Kxh8 10.e7 Nd6 11.e8Q+ Nxe8 12.Rxe8+ Kg7 13.a3 ± (1.19) Depth: 12/41 00:07:40 486222kN 1...Qf8 2.Bxe7 Qxe7 3.Ng5+ Kg7 4.Nf7+ Kh7 5.Qf4 Kg8 6.Nxh8 Kxh8 7.Rad1 Kg8 8.Qb8+ Qf8 9.Qxf8+ Kxf8 10.e7+ Kg8 11.e8Q+ Kh7 +- (1.59) Depth: 13/41 00:07:51 497612kN 1...Qf8 2.Bxe7 Qxe7 3.Ng5+ Kg7 4.Nf7+ Kh7 5.Rad1 Rf8 6.Rd7 h4 7.Qf4 Qf6 8.Nd6+ Kg8 9.e7 Nxd6 10.Rxd6 Qf7 +- (2.25) Depth: 13/44 00:09:21 601987kN (, MyTown 01.08.2004) Uri
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