Chessmaster v Christiansen test position (2002)

[Lyudmil Tsvetkov]

I am inclined to think black wins that.

Rg3 migth still be the winning move, only black should not hurry.
Black can improve, while white can not do basically anything useful, so first black should get rid of its low mobility rooks (allowing some tricks with the white bishop along the h3-c8 diagonal, trapping the g4 rook) and awkward king placement.

Immediately playing Rg3 is a draw, too few material, but why not first improve with 1...Rh5, followed by Kg7, and only then Rg3?

I think above plan is winning, or at least white should toil and moil for a hundreth moves for a draw.

[Maarten Claessens]

Perhaps Larry saw something that the engines didn't, it would have been cool if Larry had demonstrated the win after 53...Rg3 for further scrutiny.

Seems Larry analyzed the game in CM10k Academy (see this page on chessgames.com). These lines are quoted there:

Code: Select all

<He gives 53...Rg3 a !

If 55.Rf3 Rh5 56.Kg1 Rh2 57.Kf1 Qh5 58.Rd2 Rh1 59.Ke2 Rg1!

55...Rg4? - better is 55...Rh5 56.Kg1 Rh2 57.Qf3 Kg5! 58.Kf1 Nh4 58.Qb3 f3 59.gxf3 g2 60.Rxg2 Nxg2 "and White is in big trouble"

57...Qh1 58.Ke2 Qxg2 59.Ke1 Qh1 60.Kd2 g2 61.e5! Qxd1! 62.Qxd1 g1=Q "and Black has the upper hand"

58...f2?? - "this is not just a blunder, this is a crime" - better was 58...Rf4 59.Kd2 fxg2 60.Qe3 Kg7>

[Vinvin]

Perhaps Larry saw something that the engines didn't, it would have been cool if Larry had demonstrated the win after 53...Rg3 for further scrutiny.

Seems Larry analyzed the game in CM10k Academy (see this page on chessgames.com). These lines are quoted there:

Code: Select all

<He gives 53...Rg3 a !

If 55.Rf3 Rh5 56.Kg1 Rh2 57.Kf1 Qh5 58.Rd2 Rh1 59.Ke2 Rg1!

Stockfish thinks 57.Kf1?? is big mistake (-7.83) and prefers 57.Rdd3 (0.00) , ready to give back the rook with Rxg3 fxg3 Rxg3.

[tpoppins]

Here is the position analyzed before the key move was played.
It appears that (according to SF) the best move is Qf6 which draws. It appears that Rg3 and Rh5 also draw.

Since most everyone chose SF, maybe we should re-examine with a different engine.

[d]8/p1p5/Pp1p2nk/1P1Bq1r1/2P1Pprp/1Q6/5RPP/3R3K b - - 0 53

Code: Select all

Analysis by Komodo 10.1 64-bit:

1. = (-0.22): 53...Qf6 54.Rdf1 Rg3 55.Qd1 Kg7 56.Qe2 Qe5 57.Rf3 Rxg2 58.Qxg2 Rxg2 59.Kxg2 Qf6 60.Kh3 Kf8 61.R1f2 Ke7 62.Rf1 Kd7 63.R1f2 Kd8 64.Rf1 Ke7 65.Kg2 Qe5 66.R1f2 Qh5 67.Kh3 Qh6 68.Kg2 Kd7 69.Kh3 Kd8 70.Rf1 Ke7 71.Kg2 Qf8 72.R3f2 Qg7 
2. = (0.00): 53...h3 54.Qxh3+ Rh4 55.Qb3 Rg3 56.Rd3 Qd4 57.Rxd4 Rxb3 58.Rd1 Ne5 59.Kg1 Rc3 60.Rff1 Kg5 61.Rc1 Re3 62.Rce1 Rxe1 63.Rxe1 Rh6 64.Rf1 Kg4 65.Rf2 Rf6 66.Rf1 f3 67.g3 Kh3 68.Bb7 Rf8 69.Bd5 Rf6 
Depth: 35   08:08:03  592939 MN

This analysis was done with null-move pruning off, hence the relatively low depth.
Single-PV, same settings, after 53...Rg3:

Code: Select all

54.hxg3 hxg3 
  +- (3.53 --)  Depth: 7   00:00:00  37kN
54.hxg3 hxg3 
  +- (3.44 --)  Depth: 7   00:00:00  39kN
54.Qxg3 
  +- (3.45 --)  Depth: 7   00:00:00  40kN
54.Qxg3 hxg3 
  +- (3.33 --)  Depth: 7   00:00:00  42kN
54.Qxg3 hxg3 
  +- (3.15 --)  Depth: 7   00:00:00  48kN
54.hxg3 hxg3 55.Rfd2 
  +- (3.50 ++)  Depth: 7   00:00:00  52kN
54.hxg3 hxg3 
  +- (3.19 --)  Depth: 7   00:00:00  55kN
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Nh4 57.Rff1 
  +- (3.19)  Depth: 7   00:00:00  59kN
54.hxg3 hxg3 
  +- (3.11 --)  Depth: 8   00:00:00  64kN
54.hxg3 hxg3 
  +- (3.03 --)  Depth: 8   00:00:00  67kN
54.hxg3 hxg3 
  +- (2.89 --)  Depth: 8   00:00:00  72kN
54.hxg3 hxg3 55.Rf3 Qf6 56.Kg1 Ne5 57.Kf1 Rh5 58.Qb2 
  +- (2.77)  Depth: 8   00:00:00  77kN
54.hxg3 hxg3 
  +- (2.69 --)  Depth: 9   00:00:00  94kN
54.hxg3 hxg3 
  +- (2.54 --)  Depth: 9   00:00:00  97kN
54.hxg3 hxg3 
  +- (2.36 --)  Depth: 9   00:00:00  152kN
54.hxg3 hxg3 
  +- (1.91 --)  Depth: 9   00:00:00  155kN
54.hxg3 hxg3 
  +- (1.63 --)  Depth: 9   00:00:00  168kN
54.hxg3 hxg3 55.Rb2 
  +- (2.00 ++)  Depth: 9   00:00:00  180kN
54.hxg3 hxg3 55.Rb2 f3 56.gxf3 Nf4 57.Rdd2 Kg7 58.Qe3 Kh6 
  +- (2.02)  Depth: 9   00:00:00  183kN
54.hxg3 hxg3 
  +- (1.95 --)  Depth: 10   00:00:00  201kN
54.hxg3 hxg3 
  +- (1.88 --)  Depth: 10   00:00:00  212kN
54.hxg3 hxg3 
  +- (1.78 --)  Depth: 10   00:00:00  216kN
54.hxg3 hxg3 
  +- (1.63 --)  Depth: 10   00:00:00  219kN
54.hxg3 hxg3 
  +/- (1.41 --)  Depth: 10   00:00:00  225kN
54.hxg3 hxg3 55.Ra2 
  +/- (1.57 ++)  Depth: 10   00:00:00  260kN
54.hxg3 hxg3 55.Ra2 
  +- (2.06 ++)  Depth: 10   00:00:00  269kN
54.hxg3 hxg3 
  +- (1.69 --)  Depth: 10   00:00:00  295kN
54.hxg3 hxg3 55.Ra2 Rh5+ 56.Kg1 Rh2 57.Qf3 Qg5 58.Kf1 Ne5 59.Qb3 Qg4 60.Ke1 Qh5 
  +/- (1.02)  Depth: 10   00:00:00  335kN
54.hxg3 hxg3 55.Rf3 
  +/- (1.09 ++)  Depth: 11   00:00:00  375kN
54.hxg3 hxg3 
  +/- (1.02 --)  Depth: 11   00:00:00  380kN
54.hxg3 hxg3 
  +/- (0.92 --)  Depth: 11   00:00:00  391kN
54.hxg3 hxg3 55.Ra2 
  +/- (1.00 ++)  Depth: 11   00:00:00  408kN
54.hxg3 hxg3 
  +/- (0.88 --)  Depth: 11   00:00:00  428kN
54.hxg3 hxg3 55.Ra2 Rh5+ 56.Kg1 Rh2 57.Qf3 Qg5 58.Kf1 Ne5 59.Qb3 Rh1+ 60.Ke2 f3+ 61.Qxf3 Nxf3 62.Rxh1+ 
  +/- (0.88)  Depth: 11   00:00:00  435kN
54.hxg3 hxg3 55.Ra2 Rh5+ 56.Kg1 Rh2 57.Qf3 Qg5 58.Kf1 Ne5 59.Qb3 Rh1+ 60.Ke2 f3+ 61.Qxf3 Nxf3 62.Rxh1+ Nh2 63.Kd3 Qe5 
  +/- (0.88)  Depth: 12   00:00:00  492kN
54.hxg3 hxg3 
  +/- (0.81 --)  Depth: 13   00:00:00  531kN
54.hxg3 hxg3 
  +/- (0.74 --)  Depth: 13   00:00:00  648kN
54.hxg3 hxg3 
  +/= (0.64 --)  Depth: 13   00:00:00  705kN
54.hxg3 hxg3 55.Ra2 Rh5+ 56.Kg1 Rh2 57.Kf1 Qh5 58.Ke1 Ne5 59.Kd2 Rxg2+ 60.Kc1 Rh2 61.Rxh2 Qxh2 62.Re1 g2 63.Qd1 Qg3 64.Kb1 Qd3+ 
  +/= (0.53)  Depth: 13   00:00:00  1058kN
54.hxg3 hxg3 
  +/= (0.46 --)  Depth: 14   00:00:00  1147kN
54.hxg3 hxg3 
  +/= (0.39 --)  Depth: 14   00:00:00  1205kN
54.hxg3 hxg3 
  = (0.29 --)  Depth: 14   00:00:00  1256kN
54.hxg3 hxg3 
  = (0.14 --)  Depth: 14   00:00:00  1428kN
54.hxg3 hxg3 
  = (-0.08 --)  Depth: 14   00:00:00  1654kN
54.hxg3 hxg3 55.Ra2 Rh5+ 56.Kg1 Rh2 57.Kf1 Qh5 58.Ke1 Ne5 59.Kd2 Rxg2+ 60.Kc1 Rh2 61.c5 bxc5 62.Bg8 Rxa2 63.Qxa2 f3 64.Qe6+ Kg7 
  = (-0.08)  Depth: 14   00:00:00  1782kN
54.hxg3 hxg3 
  = (-0.15 --)  Depth: 15   00:00:00  2243kN
54.hxg3 hxg3 55.Ra2 
  = (-0.08 ++)  Depth: 15   00:00:00  2495kN
54.hxg3 hxg3 55.Ra2 
  = (0.02 ++)  Depth: 15   00:00:00  3014kN
54.hxg3 hxg3 
  = (-0.06 --)  Depth: 15   00:00:00  3516kN
54.hxg3 hxg3 55.Ra2 Rh5+ 56.Kg1 Qg5 57.Kf1 Ne5 58.Be6 Rh1+ 59.Ke2 Rh2 60.Rf1 Rxg2+ 61.Kd1 Rxa2 62.Qxa2 g2 63.Rg1 Qh5+ 64.Kc1 f3 65.Qc2 
  = (-0.11)  Depth: 15   00:00:00  3545kN
54.hxg3 hxg3 
  = (-0.17 --)  Depth: 16   00:00:00  4630kN
54.hxg3 hxg3 
  = (-0.23 --)  Depth: 16   00:00:00  4700kN
54.hxg3 hxg3 
  =/+ (-0.32 --)  Depth: 16   00:00:00  4966kN
54.hxg3 hxg3 
  =/+ (-0.45 --)  Depth: 16   00:00:00  7234kN
54.hxg3 hxg3 
  =/+ (-0.64 --)  Depth: 16   00:00:01  7591kN
54.hxg3 hxg3 
  -/+ (-0.92 --)  Depth: 16   00:00:01  8759kN
54.Qc2 Re3 55.Rdf1 h3 56.gxh3 Rxh3 57.Qe2 Rgh5 58.Rf3 Rxf3 59.Qxf3 Qb2 60.Qf2 Qxf2 61.Rxf2 Rh4 62.Kg1 Kg5 63.Kf1 Ne5 64.Rg2+ 
  -/+ (-0.91)  Depth: 16   00:00:01  18636kN
54.Qc2 Re3 
  -/+ (-0.97 --)  Depth: 17   00:00:02  26799kN
54.Qa2 Re3 55.Rdf1 
  -/+ (-0.85 ++)  Depth: 17   00:00:03  34769kN
54.Qa2 Re3 55.Rdf1 Qc3 56.Qb1 h3 57.gxh3 Rxh3 58.Be6 Re3 59.Qd1 Rxe4 60.Bd5 Re7 61.Qb1 Re3 62.Qd1 Rd3 63.Qa1 Qe5 64.Qxe5 dxe5 65.Be4 
  -/+ (-0.89)  Depth: 17   00:00:03  36975kN
54.Qa2 Re3 55.Rdf1 
  -/+ (-0.83 ++)  Depth: 18   00:00:03  38457kN
54.Qa2 Re3 55.Rdf1 
  -/+ (-0.77 ++)  Depth: 18   00:00:03  39830kN
54.Qa2 Re3 55.Rdf1 h3 56.gxh3 Qc3 57.Qb1 Rxh3 58.Be6 Re3 59.Qd1 Rxe4 60.Rf3 Qe5 61.Bf7 Kg7 62.Bd5 Re3 63.Rg1 Rxg1+ 64.Qxg1 Re1 65.Rf1 Rxf1 66.Qxf1 Qd4 
  -/+ (-0.82)  Depth: 18   00:00:03  43232kN
54.hxg3 hxg3 55.Rf3 
  =/+ (-0.68 ++)  Depth: 18   00:00:03  45732kN
54.hxg3 hxg3 55.Rf3 
  =/+ (-0.55 ++)  Depth: 18   00:00:04  47000kN
54.hxg3 hxg3 55.Rf3 
  =/+ (-0.36 ++)  Depth: 18   00:00:04  49794kN
54.hxg3 hxg3 55.Rf3 
  = (-0.08 ++)  Depth: 18   00:00:04  51417kN
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 Qb3+ 65.Ke2 Re5+ 66.Kf1 Qe3 67.Qxe3 Rxe3 68.Kg2 Kg5 69.Rf1 Kg4 
  = (-0.04)  Depth: 18   00:00:04  54337kN
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 Qb3+ 65.Kd2 Qxf3 66.Bxf3 Rg6 67.Rh1+ Kg5 68.Ke2 Re6+ 69.Kf1 Re3 70.Kg2 Rc3 71.Rh5+ Kg6 72.Rh8 Rc2+ 
  = (-0.09)  Depth: 19   00:00:05  65168kN, tb=2
54.hxg3 hxg3 
  = (-0.15 --)  Depth: 20   00:00:05  67163kN, tb=3
54.hxg3 hxg3 
  = (-0.21 --)  Depth: 20   00:00:05  71641kN, tb=5
54.hxg3 hxg3 
  = (-0.30 --)  Depth: 20   00:00:05  73478kN, tb=5
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Re1 Qh2 64.Qc1 g2 65.Rg1 Qh4 66.Rxg2 Nxf3+ 67.Bxf3 Rxg2 68.Bxg2 Qf2+ 69.Kd3 Qxg2 70.Qxf4+ Qg5 71.Qf8+ Kh5 72.Qf7+ Kg4 73.Qxc7 Qf5+ 74.Kc3 Qe5+ 
  = (-0.30)  Depth: 20   00:00:05  75654kN, tb=7
54.hxg3 hxg3 55.Rf3 
  = (-0.24 ++)  Depth: 21   00:00:06  90539kN, tb=11
54.hxg3 hxg3 55.Rf3 
  = (-0.18 ++)  Depth: 21   00:00:07  99939kN, tb=13
54.hxg3 hxg3 
  = (-0.24 --)  Depth: 21   00:00:07  105MN, tb=15
54.hxg3 hxg3 
  =/+ (-0.37 --)  Depth: 21   00:00:08  108MN, tb=15
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Rdf1 Qh2 64.Qc1 g2 65.Rg1 Qh4 66.Rxg2 Nxf3+ 67.Bxf3 Rxg2 68.Bxg2 Qf2+ 69.Kd3 Qg3+ 70.Kd4 Qxg2 71.Qxf4+ Kg7 72.Qe3 Kf7 73.Kc3 Qg6 74.Qe2 
  =/+ (-0.36)  Depth: 21   00:00:08  116MN, tb=17
54.hxg3 hxg3 
  =/+ (-0.42 --)  Depth: 22   00:00:10  139MN, tb=39
54.hxg3 hxg3 55.Rf3 
  =/+ (-0.36 ++)  Depth: 22   00:00:11  162MN, tb=51
54.hxg3 hxg3 
  =/+ (-0.42 --)  Depth: 22   00:00:11  164MN, tb=51
54.hxg3 hxg3 
  =/+ (-0.55 --)  Depth: 22   00:00:12  173MN, tb=62
54.hxg3 hxg3 
  -/+ (-0.74 --)  Depth: 22   00:00:14  197MN, tb=85
54.hxg3 hxg3 55.Rf3 
  =/+ (-0.59 ++)  Depth: 22   00:00:14  205MN, tb=91
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Re1 Qh2 64.Qc1 Kg7 65.Qd1 Kf8 66.Kc3 g2 67.Qd4 g1Q 68.Rxg1 Rxg1 69.Qxf4+ Qxf4 70.Rxf4+ Kg7 71.Rh4 Rg3+ 72.Kd4 Rg4+ 73.Rxg4+ Nxg4 74.Ke4 Ne5 75.Be6 Kf6 76.Bd5 
  =/+ (-0.56)  Depth: 22   00:00:14  205MN, tb=91
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Re1 Qh2 64.Qc1 Kg7 65.Qd1 Kf8 66.Kc3 g2 67.Qd4 g1Q 68.Rxg1 Rxg1 69.Qxf4+ Qxf4 70.Rxf4+ Kg7 71.Rh4 Rg3+ 72.Kd4 Rg4+ 73.Rxg4+ Nxg4 74.Ke4 Ne5 75.Be6 Kf6 76.Bd5 Kg5 
  =/+ (-0.56)  Depth: 23   00:00:18  263MN, tb=256
54.hxg3 hxg3 
  =/+ (-0.62 --)  Depth: 24   00:00:19  279MN, tb=281
54.hxg3 hxg3 
  =/+ (-0.68 --)  Depth: 24   00:00:20  289MN, tb=285
54.hxg3 hxg3 55.Rf3 
  =/+ (-0.62 ++)  Depth: 24   00:00:24  360MN, tb=468
54.hxg3 hxg3 55.Rf3 
  =/+ (-0.49 ++)  Depth: 24   00:00:29  437MN, tb=694
54.hxg3 hxg3 55.Rf3 
  = (-0.30 ++)  Depth: 24   00:00:34  514MN, tb=879
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Re1 Qh2 64.Qc1 g2 65.Rg1 Qh4 66.Rxg2 Nxf3+ 67.Bxf3 Rxg2 68.Bxg2 Qf2+ 69.Kc3 Qg3+ 70.Kd4 Qxg2 71.Qxf4+ Kg7 72.Kc3 Qh3+ 73.Kb4 Qh5 74.Kb3 Qd1+ 75.Kc3 Qa1+ 76.Kb3 Qb1+ 77.Kc3 Qg6 78.Kb4 
  = (-0.30)  Depth: 24   00:00:36  542MN, tb=923
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Re1 Qh2 64.Qc1 g2 65.Rg1 Qh4 66.Rxg2 Nxf3+ 67.Bxf3 Rxg2 68.Bxg2 Qf2+ 69.Kc3 Qg3+ 70.Kd4 Qxg2 71.Qxf4+ Kg7 72.Kc3 Qh3+ 73.Kb4 Qh5 74.Kb3 Qd1+ 75.Kc3 Qa1+ 76.Kb3 Qb1+ 77.Kc3 Kg6 78.Qg3+ Kf6 79.Qg8 
  =/+ (-0.34)  Depth: 25   00:00:46  704MN, tb=1858
54.hxg3 hxg3 
  =/+ (-0.40 --)  Depth: 26   00:00:51  786MN, tb=2697
54.hxg3 hxg3 55.Rf3 
  =/+ (-0.34 ++)  Depth: 26   00:01:02  940MN, tb=3375
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Re1 Qh2 64.Qc1 g2 65.Rg1 Qh4 66.Rxg2 Nxf3+ 67.Bxf3 Rxg2 68.Bxg2 Qf2+ 69.Kc3 Qg3+ 70.Kd4 Qxg2 71.Qxf4+ Kg7 72.Kc3 Qh3+ 73.Kb4 Qh5 74.Kb3 Qd1+ 75.Kb4 Qe1+ 76.Kb3 Qb1+ 77.Kc3 Kg6 78.Qg4+ Kf6 
  = (-0.29)  Depth: 26   00:01:09  1053MN, tb=4055
54.hxg3 hxg3 55.Rf3 
  = (-0.23 ++)  Depth: 27   00:01:36  1463MN, tb=9460
54.hxg3 hxg3 55.Rf3 
  = (-0.17 ++)  Depth: 27   00:01:51  1711MN, tb=10879
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Be4 Qh2 64.Rff1 Kg5 65.Rh1 Qf2+ 66.Kd5 g2 67.Rh7 Rg3 68.Qd4 Qxd4+ 69.Kxd4 f3 70.Rxc7 Kf4 71.Rxa7 g1Q+ 72.Rxg1 Rxg1 73.Bxf3 Kxf3 74.Kd5 Rd1+ 75.Ke6 Nxc4 76.Rc7 Ne5 77.a7 Ra1 78.Rb7 
  = (-0.11)  Depth: 27   00:01:58  1832MN, tb=11152
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Be4 Qh2 64.Rff1 Kg5 65.Rh1 Qf2+ 66.Kd5 g2 67.Rh7 Rg3 68.Qd4 Qxd4+ 69.Kxd4 f3 70.Rxc7 Kf4 71.Rxa7 g1Q+ 72.Rxg1 Rxg1 73.Bxf3 Kxf3 74.Kd5 Rd1+ 75.Ke6 Nxc4 76.Rc7 Ne5 77.a7 Ra1 78.Rb7 Nd3 
  = (-0.11)  Depth: 28   00:02:18  2149MN, tb=14460
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Be4 Qh2 64.Rff1 Kg5 65.Rh1 Qf2+ 66.Kd5 g2 67.Rh7 Rg3 68.Qd4 Qxd4+ 69.Kxd4 f3 70.Rxc7 Kf4 71.Rxa7 g1R 72.Rxg1 Rxg1 73.Bxf3 Kxf3 74.Kd5 Rd1+ 75.Ke6 Nxc4 76.Rc7 Ne5 77.a7 Ra1 78.Rb7 Nd3 
  = (-0.11)  Depth: 29   00:02:37  2456MN, tb=18846
54.hxg3 hxg3 55.Rf3 
  = (-0.05 ++)  Depth: 30   00:03:43  3666MN, tb=37715
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Be4 Qh2 64.Rff1 Kg5 65.Rh1 Qf2+ 66.Kd5 g2 67.Rh7 Rg3 68.Qd4 Qxd4+ 69.Kxd4 f3 70.Rxc7 Kf4 71.Rxa7 g1Q+ 72.Rxg1 Rxg1 73.Bxf3 Kxf3 74.Rb7 Rd1+ 75.Kc3 Rc1+ 76.Kb3 Kf4 77.Rxb6 Rb1+ 78.Kc3 Rc1+ 79.Kb3 
  = (0.00)  Depth: 30   00:04:21  4392MN, tb=45386
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Be4 Qh2 64.Rff1 Kg5 65.Rh1 Qf2+ 66.Kd5 g2 67.Rh7 Rg3 68.Qd4 Qxd4+ 69.Kxd4 f3 70.Rxc7 Kf4 71.Rxa7 g1Q+ 72.Rxg1 Rxg1 73.Bxf3 Kxf3 74.Rb7 Rd1+ 75.Kc3 Rc1+ 76.Kb3 Kf4 77.Rxb6 Rb1+ 78.Kc3 Rc1+ 79.Kb3 
  = (0.00)  Depth: 31   00:05:16  5462MN, tb=78031
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Be4 Qh2 64.Rff1 Kg5 65.Rh1 Qf2+ 66.Kd5 g2 67.Rh7 Kf6 68.Rh6+ Kf7 69.Rh7+ Rg7 70.Rxg7+ Kxg7 71.Qe1 Qc5+ 72.Ke6 Qxc4+ 73.Rd5 c6 74.bxc6 Qxc6 75.Rxd6 Qe8+ 76.Kd5 Qb5+ 77.Ke6 Qe8+ 
  = (0.00)  Depth: 32   00:06:43  7170MN, tb=144865
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Be4 Qh2 64.Rff1 Kg5 65.Rh1 Qf2+ 66.Kd5 g2 67.Rh7 Kf6 68.Rh6+ Kf7 69.Rh7+ Rg7 70.Rxg7+ Kxg7 71.Qe1 Qc5+ 72.Ke6 Qxc4+ 73.Rd5 c6 74.bxc6 Qxc6 75.Rxd6 Qe8+ 76.Kd5 Qb5+ 77.Ke6 Qe8+ 
  = (0.00)  Depth: 33   00:08:53  9729MN, tb=279815
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Be4 Qh2 64.Rff1 Kg5 65.Rh1 Qf2+ 66.Kd5 g2 67.Rh7 Kf6 68.Rh6+ Kf7 69.Rh7+ Rg7 70.Rxg7+ Kxg7 71.Qe1 Qc5+ 72.Ke6 Qxc4+ 73.Rd5 c6 74.bxc6 Qxc6 75.Rxd6 Qe8+ 76.Kd5 Qb5+ 77.Ke6 Nf7 78.Qc3+ Kf8 79.Qc8+ Kg7 80.Qc3+ 
  = (0.00)  Depth: 34   00:12:26  13951MN, tb=588287
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Be4 Qh2 64.Rff1 Kg5 65.Rh1 Qf2+ 66.Kd5 g2 67.Rh7 Kf6 68.Rh6+ Kf7 69.Rh7+ Rg7 70.Rxg7+ Kxg7 71.Qe1 Qc5+ 72.Ke6 Qxc4+ 73.Rd5 c6 74.bxc6 Qxc6 75.Rxd6 Qe8+ 76.Kd5 Qb5+ 77.Ke6 Nf7 78.Qc3+ Kf8 79.Qc8+ Kg7 80.Qc3+ 
  = (0.00)  Depth: 35   00:19:02  21820MN, tb=1230888
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Be4 Qh2 64.Rff1 Kg5 65.Rh1 Qf2+ 66.Kd5 g2 67.Rh7 Kf6 68.Rh6+ Kf7 69.Rh7+ Rg7 70.Rxg7+ Kxg7 71.Qe1 Qc5+ 72.Ke6 Qxc4+ 73.Rd5 c6 74.bxc6 Qxc6 75.Rxd6 Qe8+ 76.Kd5 Qb5+ 77.Ke6 Nf7 78.Qc3+ Kf8 79.Qc8+ Kg7 80.Rd5 Qb2 81.Bxg2 Qxg2 82.Qc3+ Kg8 83.Qc8+ Kg7 
  = (0.00)  Depth: 36   00:28:18  32914MN, tb=2590090
54.hxg3 hxg3 55.Rf3 Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Rg4 63.Be4 Qh2 64.Rff1 Kg5 65.Rh1 Qf2+ 66.Kd5 g2 67.Rh7 Rg3 68.Qd4 Qxd4+ 69.Kxd4 f3 70.Rxc7 Rh3 71.Bxf3 Nxf3+ 72.Ke3 g1Q+ 73.Rxg1+ Nxg1+ 74.Ke4 Rh4+ 75.Kd5 Ne2 76.Rxa7 Nc3+ 77.Kxd6 Rxc4 78.Rb7 Rc5 79.Rxb6 Rxb5 
  = (0.00)  Depth: 37   00:45:44  53735MN, tb=5425828

and three plies (from the above PV) deeper:

Code: Select all

55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 
  = (0.00)  Depth: 7   00:00:00  9kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 
  = (0.00)  Depth: 8   00:00:00  11kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 
  = (0.00)  Depth: 9   00:00:00  18kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 
  = (0.00)  Depth: 10   00:00:00  27kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ 
  = (0.00)  Depth: 11   00:00:00  34kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ 
  = (0.00)  Depth: 12   00:00:00  44kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ 
  = (0.00)  Depth: 13   00:00:00  64kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 
  = (0.00)  Depth: 14   00:00:00  102kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ 
  = (0.00)  Depth: 15   00:00:00  216kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 
  = (0.00)  Depth: 16   00:00:00  289kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 17   00:00:00  450kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qxf4 Qb3+ 74.Kd2 
  = (0.00)  Depth: 18   00:00:00  628kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qxf4 Qb3+ 74.Kd2 Qb2+ 75.Kd3 
  = (0.00)  Depth: 19   00:00:00  966kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 20   00:00:00  1530kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 21   00:00:00  2289kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 22   00:00:00  3156kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 23   00:00:00  4327kN
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 24   00:00:00  6222kN, tb=2
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 25   00:00:00  8764kN, tb=6
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 26   00:00:01  13979kN, tb=6
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 27   00:00:01  28861kN, tb=70
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 28   00:00:02  44082kN, tb=133
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 29   00:00:03  60585kN, tb=380
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 30   00:00:04  88462kN, tb=899
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 31   00:00:12  251MN, tb=6976
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 32   00:00:17  352MN, tb=13612
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 33   00:00:53  1084MN, tb=85695
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 34   00:01:56  2331MN, tb=243617
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 35   00:04:48  5754MN, tb=836082
55...Rg4 56.Kg1 Qh5 57.e5 Rg5 58.Qc3 Qh2+ 59.Kf1 Qh1+ 60.Ke2 Qxg2+ 61.Kd3 Nxe5+ 62.Kd4 Nxf3+ 63.Qxf3 Qb2+ 64.Kd3 g2 65.Qh3+ Kg7 66.Qd7+ Kh6 67.Qe6+ Rg6 68.Qh3+ Kg7 69.Qd7+ Kf6 70.Qd8+ Kg7 71.Qe7+ Kh6 72.Qh4+ Kg7 73.Qe7+ 
  = (0.00)  Depth: 36   00:19:44  23623MN, tb=3862940

Provided Black doesn't play something ridiculous (like 55.Ra2 in the game), it looks to be a draw.

[Vinvin]

I spent some time again on this position.
Conclusions :
1) The eval still equal after 53...Rg3.
2) 55.Ra2 is a mistake. Only 55.Rf3 seems to hold the equality.
3) The good move to refute 55.Ra2 is 55...Rh5+. Modern engines find it rather quickly :

Code: Select all

FEN: 8/p1p5/Pp1p2nk/1P1Bq1r1/2P1Pp2/1Q4p1/R5P1/3R3K b - - 1 55

Cfish 2019-07-17 64 BMI2:
...
 22/19	00:00	 3.911k	7.609k	 0,00	55. ... Rg4 56.Kg1 Qh5 57.Kf1 Qh1+ 58.Ke2 Qxg2+ 59.Kd3 Qf3+ 60.Kc2 Qxb3+ 61.Kxb3 f3 62.e5 Nxe5 63.Rf1 Rf4 64.Rg1 Rg4
 23/37	00:00	 6.425k	7.760k	-0,58	55. ... Rh5+ 56.Kg1 Qg5 57.Kf1 Ne5 58.Be6 Rh2 59.Bh3 Rh1+ 60.Ke2 f3+ 61.Qxf3 Nxf3 62.Rxh1 Nd4+ 63.Kd3 Nb3 64.Bf5+ Kg7 65.Rc2 Kf6 66.Rf1 Ke5 67.Bc8 Nc5+ 68.Ke2 Kd4 69.Rf3 Qh5 70.Bf5 Ke5 71.Ke3
 24/46	00:01	 8.488k	7.867k	-0,94	55. ... Rh5+ 56.Kg1 Rh2 57.Qf3 Qg5 58.Be6 Ne5 59.Qb3 f3 60.c5 Qf4 61.Rf1 Qxe4 62.Bh3 Qd4+ 63.Raf2 Rxh3 64.Qe6+ Kg5 65.Qxh3 gxf2+ 66.Kh1 fxg2+ 67.Kxg2 Ng4 68.cxb6 cxb6 69.Qg3 Qe4+ 70.Kh3 Qe2 71.Kg2 Kf5 72.Qf3+ Qxf3+ 73.Kxf3 Nh2+ 74.Kxf2 Nxf1 75.Kxf1 Ke4 76.Ke2
 25/53	00:02	 16.609k	7.901k	-1,17	55. ... Rh5+ 56.Kg1 Rh2 57.Qf3 Qg5 58.Be6 Nh4 59.Qc3 Qc5+ 60.Rd4 Nf3+ 61.gxf3 Rxa2 62.Bf5 Kg7 63.Kh1 Rh2+ 64.Kg1 Kf8 65.Kf1 Kf7 66.Kg1 Ra2 67.Kh1 Ra3 68.Qb2 Rxf3 69.Rd1 Rf2 70.Qd4 Qxd4
 26/47	00:02	 17.763k	7.881k	-1,41	55. ... Rh5+ 56.Kg1 Rh2 57.Qf3 Qg5 58.Be6 Nh4 59.Qc3 Qc5+ 60.Rd4 Nf3+ 61.gxf3 Rxa2 62.Bd5 Ra3 63.Qd2 Rxf3 64.Qd1 Qa3 65.Qe1 Kg5 66.e5 Re3 67.Qd2 dxe5 68.Re4 Qa1+ 69.Kg2 Rb3 70.Re1 Rb2 71.Rxa1 Rxd2+ 72.Kf3 Rf2+ 73.Ke4 f3 74.Rd1 g2 75.Kxe5 Re2+ 76.Kd4
 27/49	00:03	 24.296k	7.917k	-2,63	55. ... Rh5+ 56.Kg1 Rh2 57.Qf3 Qg5 58.Be6 Nh4 59.Qc3 Qc5+ 60.Rd4 Nf3+ 61.gxf3 Rxa2 62.Bf5 Kg7 63.Kh1 Rh2+ 64.Kg1 Kf8 65.Kf1 Rf2+ 66.Kg1 Ra2 67.Bg4 Kf7 68.Bh3 Ra3 69.Qd2 Rxf3 70.Qd1 Ra3 71.Qd2 Ke7 72.Bf5 Qe5 73.Rd3 Rxd3 74.Qxd3
 28/48-	00:03	 27.463k	7.930k	-2,72	55. ... Rh5+
 28/48-	00:03	 27.718k	7.926k	-2,82	55. ... Rh5+
 28/56-	00:03	 30.128k	7.893k	-3,15	55. ... Rh5+
 28/56	00:03	 30.310k	7.893k	-3,16	55. ... Rh5+ 56.Kg1 Rh2 57.Qf3 Qg5 58.Be6 Nh4 59.Qc3 Qc5+ 60.Rd4 Nf3+ 61.gxf3 Rxa2 62.Bf5 Kg7 63.Kh1 Rh2+ 64.Kg1 Kf8 65.Bg4 Ra2 66.Kf1 Rf2+ 67.Kg1 Rh2 68.Bf5 Ra2 69.Bg4 Kf7 70.Kh1 Rh2+ 71.Kg1 Qg5 72.Rd5 Qh6 73.Rf5+ Kg8 74.Rh5 Rxh5 75.Bxh5 Qxh5
 29/52-	00:03	 31.463k	7.887k	-3,25	55. ... Rh5+
 29/52-	00:04	 33.039k	7.902k	-3,35	55. ... Rh5+
 29/52-	00:04	 33.674k	7.907k	-3,49	55. ... Rh5+
 29/52	00:04	 34.739k	7.908k	-3,38	55. ... Rh5+ 56.Kg1 Rh2 57.Kf1 Nh4 58.Rd3 Rh1+ 59.Ke2 Nxg2 60.Rd1 Rh2 61.Kd3 f3 62.Rxg2 Rxg2 63.Rf1 Rb2 64.Qd1 g2 65.Rxf3 Qg5 66.e5 g1Q 67.Rf6+ Qxf6 68.Qxg1 Qxe5 69.Qe3+ Qxe3+ 70.Kxe3 Kg5 71.Bc6 Kf5 72.Kd4 Kf4 73.Kd5 Ke3 74.Ke6 Kd4 75.Kd7
 30/34-	00:04	 36.942k	7.909k	-3,47	55. ... Rh5+
 30/51+	00:05	 40.343k	7.924k	-3,29	55. ... Rh5+ 56.Kg1
 30/51-	00:05	 41.521k	7.930k	-3,43	55. ... Rh5+
 30/51-	00:05	 46.078k	7.959k	-3,89	55. ... Rh5+
 30/51	00:06	 47.948k	7.979k	-3,96	55. ... Rh5+ 56.Kg1 Rh2 57.Kf1 Nh4 58.Rd3 Rh1+ 59.Ke2 Nxg2 60.Rd1 Rh2 61.Kd3 f3 62.Rxg2 Rxg2 63.Rf1 Rb2 64.Qd1 g2 65.Rxf3 Qg5 66.e5 g1Q 67.Rf6+ Qxf6 68.Qxg1 Qxe5 69.Qe3+ Kg7 70.Qxe5+ dxe5 71.Ke4 Kf6 72.Kf3 Rc2 73.Ke4 Rh2 74.Kf3 Rh4
 31/34-	00:06	 50.954k	7.983k	-4,06	55. ... Rh5+
 31/38-	00:06	 53.815k	7.941k	-4,15	55. ... Rh5+
 31/50-	00:07	 57.372k	7.963k	-4,49	55. ... Rh5+
 31/135	00:07	 57.991k	7.969k	-4,11	55. ... Rh5+ 56.Kg1 Rh2 57.Kf1 Nh4 58.Rd3 Rh1+ 59.Ke2 Nxg2 60.Rd1 Rh2 61.Kd3 f3 62.Rxg2 Rxg2 63.Rf1 Rb2 64.Qd1 g2 65.Rxf3 Qg5 66.e5 g1Q 67.Rf6+ Qxf6 68.Qxg1 Qxe5 69.Qe3+ Kg7 70.Qg1+ Kf6 71.Qf1+ Qf5+ 72.Qxf5+ Kxf5 73.Kd4 Rd2+ 74.Ke3 Rh2 75.Kd4 Rh4+ 76.Ke3 Ke5 77.Kf3 Rh3+ 78.Kg4 Rc3 79.Bf7 Kd4 80.Bd5 Rxc4 81.Bxc4 Kxc4 82.Kf5 Kxb5 83.Ke6
 32/60-	00:07	 58.672k	7.973k	-4,21	55. ... Rh5+
 32/60-	00:07	 62.393k	7.963k	-4,30	55. ... Rh5+
 32/60-	00:08	 68.926k	7.975k	-4,91	55. ... Rh5+
 32/60	00:09	 72.036k	7.983k	-5,00	55. ... Rh5+ 56.Kg1 Rh2 57.Kf1 Nh4 58.Ke2 Nxg2 59.Kd3 f3 60.Rxg2 Rxg2 61.Rf1 Rb2 62.Qd1 g2 63.Rxf3 Qg5 64.e5 g1Q 65.Rf6+ Qxf6 66.Qxg1 Qxe5 67.Qe3+ Kg7 68.Qg1+ Kf6 69.Qf1+ Qf5+ 70.Qxf5+ Kxf5 71.Kd4 Rd2+ 72.Kc3 Rh2 73.Kd4 Rh4+ 74.Ke3 Ke5 75.Kf3 Rd4 76.Bg8 Rd1 77.Bd5 Rxd5 78.cxd5 Kxd5 79.Ke3 Kc5 80.Kd3
 33/50-	00:10	 81.433k	8.010k	-5,09	55. ... Rh5+
 33/52	00:11	 95.624k	8.011k	-5,16	55. ... Rh5+ 56.Kg1 Rh2 57.Kf1 Nh4 58.Rd3 Rh1+ 59.Ke2 Nxg2 60.Rd1 Rh2 61.Kd3 f3 62.Rxg2 Rxg2 63.Rf1 Rb2 64.Qd1 g2 65.Rxf3 Qg5 66.e5 g1Q 67.Rf6+ Qxf6 68.Qxg1 Qxe5 69.Qe3+ Kg7 70.Qg1+ Kf6 71.Qf1+ Qf5+ 72.Qxf5+ Kxf5 73.Bc6 Ke5 74.Kc3 Re2 75.Bd5 Re3+ 76.Kb4 Rh3 77.Bc6 Rd3 78.Bd5 Rxd5 79.cxd5 Kd4 80.Ka4 Kxd5 81.Kb4
...

Shallow analysis on Lichess.org with a graph : https://lichess.org/QxzuV22w
Analysis from this time with mistakes : https://www.stmintz.com/ccc/index.php?id=257729 and http://gameknot.com/annotation.pl?gm=2239&pg=1

[zullil]

I spent some time again on this position.
Conclusions :
1) The eval still equal after 53...Rg3.
2) 55.Ra2 is a mistake. Only 55.Rf3 seems to hold the equality.

Here's what I got from Lc0 ... before it crashed ... again. Seems rather unstable for a top engine, though it might be something on my end. Hoping to find info in various log files.

[d]8/p1p5/Pp1p2nk/1P1Bq1r1/2P1Pprp/1Q6/5RPP/3R3K b - - 14 53

Code: Select all

Nodes: 83.9M, N/s: 51.1k, Time: 27m 21s

51.8% Qf6 Qb2 Qxb2 Rxb2 f3 gxf3 Rf4 Rg1 Rxg1+ Kxg1 Ne5 Rg2 Nxf3+ Kf2 Ne5+ Ke2 Rf3 Kd1 Rf1+ Kc2 h3 Rg3 Rf3 Rxf3 Nxf3 Kd3 Nxh2 Be6 Nf3 Bxh3 Kg7 Ke3 Ne5 Kd4 Kf7 Kd5 Ke7 Bc8 Kf7 Bh3 Kf8 Bf5 Ke7 Bh3 Kd8 Bf5 Ke7 Bh3 (N: 76.8M, P: 13.18%)
51.6% Rh5 Rf3 Rhg5 Rf2 Qf6 Qb2 Qxb2 Rxb2 f3 gxf3 Rf4 Rg1 Ne5 Rbg2 Rxg2 Rxg2 Rxf3 Rg8 h3 Kg1 Nd3 Rg3 Ne5 Rg8 Nd3 Rg3 Rxg3+ hxg3 Kg5 Kh2 Nf2 Be6 Kf6 Bxh3 Nxe4 Bg2 Nd2 Bd5 Nf1+ Kh3 Ne3 Kh4 Nf5+ Kg4 Ke5 Kf3 Nd4+ (N: 6.3M, P: 7.24%)
48.8% Rg3 hxg3 hxg3 Rf3 Rh5+ Kg1 Rh2 Rxg3 fxg3 Rd3 Qa1+ Rd1 Qe5 Rd3 Qa1+ Rd1 Qe5 (N: 239k, P: 8.14%)
48.5% Qe7 Rdf1 Qe5 Qh3 Kg7 Bc6 Qe6 Qb3 Ne5 Rxf4 Rxf4 Rxf4 Rg4 Rf1 Qh6 Qd1 Rf4 Bd5 Qf6 Kg1 Ng4 Rxf4 Qxf4 Qd4+ Kh7 (N: 205k, P: 7.60%)
48.8% h3 Qxh3+ Rh4 Qa3 Rgg4 Rd3 Qh5 h3 Ne5 Rb3 Qg6 Qc1 Kh7 Qf1 Kg7 Bb7 Rg3 Rxg3 Qxg3 Bc8 Kf6 Bf5 Ke7 Qe2 Rh8 Rf1 Rh4 Qf2 (N: 166k, P: 5.63%)
38.1% Ne7 Qf3 Ng6 Bf7 Kg7 Rd5 Qa1+ Rd1 Qe5 Bxg6 Rxg6 Rdf1 Qg5 h3 Rg3 Qxf4 Qxf4 Rxf4 Rxg2 Rf7+ Kh6 Rxc7 R2g3 Kh2 Rg2+ Kh1 R2g3 Rf2 Rxh3+ Rh2 Rhg3 Rxh4+ Kg5 Rch7 Kf6 R4h6 Rg1+ Kh2 Rg2+ (N: 65.2k, P: 9.90%)
38.5% Kg7 c5 h3 gxh3 Rh4 cxb6 cxb6 Rc2 Rgh5 Rc3 Ne7 Bb7 Rh6 Rg1+ Rg6 Rcc1 Rh6 Qf3 Rxg1+ Rxg1+ Rg6 Rf1 Rf6 Bc6 Ng6 Bd7 Kh6 (N: 51.9k, P: 7.66%)
37.1% Qe8 c5 bxc5 Be6 c4 Qxc4 Rc5 Qa2 Rgg5 Bf5 Qe5 h3 Ne7 b6 cxb6 Qf7 Rg7 Qf8 Kg5 Bg4 Ng6 Qd8+ Qe7 Qb8 Qc7 Qa8 Rf7 Rfd2 Rf8 Qb7 (N: 35.5k, P: 5.78%)
42.1% Kh7 Bf7 Qxe4 Qf3 Qf5 Bxg6+ Kxg6 Rdf1 h3 gxh3 Rh4 Qa8 Qe6 Qc6 Kh6 Qa8 Rg8 Qf3 Qxh3 Qxh3 Rxh3 (N: 33.6k, P: 3.61%)
36.6% f3 Qxf3 Rf4 Qe3 Rxf2 Qxf2 Rg4 Rg1 Rf4 Qe3 Qb2 g3 Qf2 Qxf2 Rxf2 gxh4 Nxh4 e5 dxe5 Re1 Ng6 Kg1 Rf4 Be4 Nh4 Bd5 Ng6 (N: 29.1k, P: 4.90%)

[MikeB]

I've dug this one up a few times since it was played almost fourteen years ago, and I don't think any engine definitively answered the question one way or another. It's been a few years since I last posted it, so I guess it's about time again....

This is a position from round 3 of Chessmaster vs. GM Larry Christiansen:

[D]8/p1p5/Pp1p2nk/1P1Bq1r1/2P1Pprp/1Q6/5RPP/3R3K b - - 0 53

At this point, Larry played 53...Rg3?! Afterwards, he claimed it was winning. But unfortunately he blundered later on in the game and lost.

But with today's powerful engines and hardware (neither of which I have), I would very much appreciate it if any of you could run this position and see if any engine can find a win for black AFTER playing Rg3. Bonus if an engine actually DOES play Rg3!

Here's the game, for your amusement:

[Event "ICC 2 120 u"]
[Site "Internet Chess Club"]
[Date "2002.09.29"]
[Round "3"]
[White "CM9000 (Botvinnik)"]
[Black "LarryC"]
[TimeControl "120+120"]
[Result "1-0"]
[ECO "A28"]

1.c4 e5 2.Nc3 Nf6 3.Nf3 Nc6 4.d4 exd4 5.Nxd4 Bb4 6.Bg5 h6 7.Bh4 Bxc3+
8.bxc3 Ne5 9.e3 d6 10.Be2 Ng6 11.Bxf6 Qxf6 12.O-O O-O 13.Qc2 Re8 14.Rfd1
Nf8 15.Bd3 Ne6 16.Nb3 Rb8 17.a4 Qe7 18.a5 Bd7 19.a6 b6 20.Nd4 Nc5 21.Nb5
Bxb5 22.cxb5 Qf6 23.Bc4 Re5 24.Bd5 Rbe8 25.Rd4 Ne6 26.Rd2 g6 27.Ra4 Kg7
28.Rd1 Re7 29.Rb4 g5 30.Bc6 Qg6 31.Qb2 f5 32.Qb1 Qf6 33.Bd5 f4 34.e4 Nf8
35.f3 h5 36.Qc2 Ng6 37.Qa2 Kh6 38.Qd2 Rg7 39.Qd4 g4 40.fxg4 Nh4 41.Rb2
Rxg4 42.Kh1 Ng6 43.Rf2 Qe7 44.Qd2 Reg5 45.Ra1 h4 46.c4 Qe5 47.Rc1 Kg7
48.Bc6 Qe7 49.Rcf1 Re5 50.Qc3 Kh6 51.Bd5 Reg5 52.Qb3 Qe5 53.Rd1 Rg3
54.hxg3 hxg3 55.Ra2 Rg4 56.Kg1 Qh5 57.Kf1 f3 58.Ke1 f2+ 59.Kd2 Rh4
60.Qe3+ Kg7 61.Rf1 Qe5 62.Kc2 Rh2 63.Qf3 Qf4 64.e5 Qxf3 65.Bxf3 Nxe5
66.Bd5 Rh5 67.Ra3 Rg5 68.Kd2 Ng6 69.Re3 Ne5 70.Ke2 Kf6 71.Rh1 Ng6 72.Rh7
1-0

Many thanks in advance,
jm

nice game, 55. Ra2 as played by white, was a mistake and Larry could have won easily with 55. ... Rh5.

I don't see anything better than draw for black - after just a few minutes, but maybe somebody will find something