a test position

[Uri Blass]

[pgn][Event "Computer chess game"]
[Site "DESKTOP-7QE6S12"]
[Date "2026.07.17"]
[Round "?"]
[White "player"]
[Black "player"]
[Result "*"]
[BlackElo "2400"]
[Time "07:48:05"]
[WhiteElo "2000"]
[TimeControl "300+3"]
[SetUp "1"]
[FEN "4r2k/5p1p/4rP2/p1P4q/3BpQ2/P1P3RP/6P1/6K1 b - - 0 1"]
[Termination "unterminated"]
[PlyCount "30"]
[WhiteType "program"]
[BlackType "human"]

1. ... e3 2. Bxe3 Rxe3 3. Rxe3 Qxc5 4. Kf2 Qb6 5. Qd4 Qb2+ 6. Kg3 Rg8+ (6.
.. Rc8 7. Qg4 Qb8+ 8. Kh4 Rg8 9. Qe4 Qf8 10. g4) 7. Kh4 Qxg2 8. Qf4 Qc6 9.
Rd3 a4 10. c4 Qc5 11. Rd7 Qg1 12. Re7 Qa1 13. c5 Qxa3 14. c6 Qc5 15. c7 a3
16. Rd7 *
[/pgn]

5.Qd4 is a winning move but I found that stockfish in analysis mode can sometimes show wrong analysis:

For example it suggests 9.c4 with a draw score instead of 9.Rd3 and needs more than a minute to change its mind.

[d]6rk/5p1p/2q2P2/p7/5Q1K/P1P1R2P/8/8 w - - 2 9



Stockfish250626:
Available processors: 0-7
Using 6 threads
NNUE evaluation using nn-f8a759c05f9f.nnue (106MiB, (83248, 1024, 31, 32, 1))
Network replica 1: Shared memory.
1/2 00:00 196 10k +0.18 c3-c4
2/5 00:00 809 43k +0.41 c3-c4
3/5 00:00 924 46k +0.48 c3-c4
4/7 00:00 3k 141k +0.45 Re3-g3 Rg8xg3 Kh4xg3 Qc6xc3+ Kg3-h4
5/8 00:00 3k 173k +0.49 Re3-g3 Rg8xg3 Kh4xg3 Qc6xc3+ Kg3-h4
6/8 00:00 4k 194k +0.49 Re3-g3 Rg8xg3 Kh4xg3 Qc6xc3+ Kg3-h4 Qc3-e1+ Kh4-h5
7/12 00:00 4k 210k +0.52 Re3-g3 Rg8xg3 Kh4xg3 Qc6xc3+ Kg3-h4 Qc3-c8
8/15 00:00 28k 1,004k +0.55 Re3-g3 Rg8xg3 Kh4xg3 Qc6xc3+ Kg3-h4 Qc3-e1+ Kh4-h5
9/15 00:00 39k 1,232k +0.60 Re3-g3 Rg8xg3 Kh4xg3 Qc6xc3+ Kg3-g4 Qc3-c8+ Kg4-h4
10/15 00:00 41k 1,296k +0.65 Re3-g3 Rg8xg3 Kh4xg3 Qc6xc3+ Kg3-g4 Qc3-c8+ Kg4-h4 Qc8-f8
11/23 00:00 179k 2,103k +0.44 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-d7 Qc5-a5 Rd7-e7 Qa5-c3 c4-c5 Qc3xa3 Re7xf7 Qa3xc5 Rf7-c7 Qc5-f8 f6-f7
12/33 00:00 257k 2,400k +0.49 Re3-g3 Rg8xg3 Kh4xg3 Qc6xc3+ Kg3-h4 Qc3-b2 a3-a4 Qb2-b6 Kh4-h5 Qb6-b1 Qf4-g5 Qb1-g6+ Kh5-h4 h7-h6 Qg5xg6 f7xg6 Kh4-g4 Kh8-g8
13/16 00:00 261k 2,375k +0.49 Re3-g3 Rg8xg3 Kh4xg3 Qc6xc3+ Kg3-h4 Qc3-b2 a3-a4 Qb2-b6 Kh4-h5 Qb6-b1 Qf4-g5 Qb1-g6+ Kh5-h4 h7-h6
14/17 00:00 296k 2,430k +0.49 Re3-g3 Rg8xg3 Kh4xg3 Qc6xc3+ Kg3-h4 Qc3-b2 a3-a4 Qb2-b6 Kh4-h5 Qb6-b1 Qf4-g5 Qb1-g6+ Kh5-h4 h7-h6 Qg5xg6 f7xg6
15/44 00:00 641k 2,726k +0.35 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-d7 Qc5-g1 Rd7-e7 Qg1-a1 c4-c5 Qa1xa3 Re7xf7 Qa3xc5 Rf7-d7 Rg8-f8 Rd7-c7 Qc5-d5 Qf4-g4 Rf8-g8 Rc7-c8 Qd5-f7 Rc8xg8+ Qf7xg8 Qg4xa4 h7-h6
16/34 00:00 816k 2,756k +0.46 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-d7 Qc5-g1 Rd7-e7 Qg1-a1 c4-c5 Qa1xa3 c5-c6 Qa3-a1 c6-c7 a4-a3 Re7-e3 a3-a2 Re3-g3 Qa1-e1 Kh4-h5 Qe1-a5+ Kh5-h6
17/28 00:00 1,595k 3,461k +0.88 Re3-d3 a5-a4 c3-c4 Rg8-e8 Rd3-d4 Qc6-b6 Rd4-d5 Qb6-e6 Rd5-b5 Qe6-e1+ Kh4-h5 Qe1-c3 h3-h4 Qc3xa3 Qf4-g5 Re8-g8
18/42 00:00 2,359k 3,681k +1.00 Re3-d3 Rg8-e8 c3-c4 a5-a4 Qf4-g5 Qc6-e4+ Kh4-h5 Qe4-g6+ Qg5xg6 f7xg6+ Kh5-h6 Kh8-g8 Rd3-d7 Re8-e3 Rd7-g7+ Kg8-f8 Kh6xh7 Re3xh3+ Kh7xg6 Rh3-g3+ Kg6-f5 Rg3xa3 c4-c5 Ra3-a1 c5-c6 a4-a3 Rg7-a7
19/23 00:00 2,979k 3,829k +1.07 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-d7 Qc5-g1 Rd7-e7 Qg1-a1 c4-c5 Qa1xa3 c5-c6 Qa3-a1
20/53 00:01 6,200k 3,776k +0.35 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-e3 Qc5-f8 Re3-e7 Rg8-g6 c4-c5 Rg6-h6+ Kh4-g3 Rh6-g6+ Kg3-f3 Qf8-c8 Kf3-e4 Rg6-g8 Qf4-f5 Qc8-b8
21/56 00:02 8,288k 3,755k +0.46 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-e3 Qc5-f8 Re3-e7 Rg8-g6 c4-c5 Rg6-h6+ Kh4-g3 Rh6-g6+ Kg3-f2 Rg6-g8 c5-c6 Qf8-c8 Qf4-e4 Qc8-b8 Kf2-e3 Rg8-g3+
22/61 00:03 13,759k 3,799k +0.12 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-d7 Qc5-g1 Rd7-e7 Qg1-a1 c4-c5 Qa1xa3 c5-c6 Qa3-c5 c6-c7 a4-a3 Re7-e1 Qc5-f8 Re1-a1 Qf8-a8 Qf4-f5 Qa8-a4+ Kh4-h5 Qa4-c6 c7-c8Q
23/59 00:05 19,804k 3,792k +0.07 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-e3 Qc5-f8 Re3-c3 Qf8-c5 Rc3-g3 Rg8xg3 Qf4xg3 Qc5-d4+ Kh4-g5 h7-h6+ Kg5-f5 Qd4-c5+ Kf5-g4 Kh8-h7 Qg3-d3+ Kh7-g8 h3-h4 Qc5-e5 Qd3-f3 h6-h5+ Kg4-h3 Kg8-h7 c4-c5 Kh7-g6 c5-c6
24/46 00:05 20,007k 3,793k +0.07 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-e3 Qc5-f8 Re3-e7 Rg8-g6 Re7-e5 Qf8-d8 c4-c5 Qd8xf6+ Qf4xf6+ Rg6xf6 Re5-e4 Rf6-c6 Re4-c4 Kh8-g8 Kh4-g5 Kg8-f8 Kg5-f5 Kf8-e7 h3-h4 Rc6-h6 Rc4-e4+ Ke7-d7 Re4xa4 Rh6-h5+ Kf5-f6 Rh5xc5 Kf6xf7 Rc5-h5 Ra4-d4+ Kd7-c6 Kf7-g7 Kc6-c5
25/53 00:06 22,694k 3,763k +0.09 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-d5 Rc6-f6 Kh4-g4 Kh8-g8 h3-h4 Kg8-f8 Rd5-d6 h6-h5+ Kg4-g5 Rf6-f3 a3-a4 Kf8-e7 Rd6-a6 f7-f6+ Kg5xh5 Rf3-f5+ Kh5-g6 Rf5xc5 Ra6-a7+ Ke7-e6 h4-h5
26/64 00:06 24,173k 3,762k +0.05 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-e3 Qc5-f8 Re3-e7 Rg8-g6 Re7-e5 Qf8-d8 c4-c5 Qd8xf6+ Qf4xf6+ Rg6xf6 Re5-e4 Rf6-c6 Re4-c4 Kh8-g8 Kh4-g4 Kg8-f8 Kg4-f5 Kf8-e7 h3-h4 Rc6-h6 Rc4-e4+ Ke7-d7 Re4xa4 Rh6-h5+ Kf5-f6 Rh5xc5 Kf6xf7 Rc5-h5 Kf7-g7
27/58 00:07 28,794k 3,770k +0.07 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-e3 Qc5-f8 Re3-e7 Rg8-g6 Re7-e5 Qf8-d8 c4-c5 Qd8xf6+ Qf4xf6+ Rg6xf6 Re5-e4 Rf6-c6 Re4-c4 Kh8-g8 Kh4-g4 Kg8-f8 Kg4-f5 Kf8-e7 h3-h4 Rc6-h6 Rc4-e4+ Ke7-d7 Re4xa4 f7-f6
28/66 00:07 29,601k 3,769k +0.05 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-d7 Qc5-g1 Rd7-e7 Qg1-a1 c4-c5 Qa1xa3 c5-c6 Qa3-c5 Re7-b7 Qc5xc6 Rb7-b8 Qc6-g2 Rb8xg8+ Qg2xg8 Qf4xa4 Qg8-d8 Qa4-f4 Qd8-b6 Kh4-h5 Qb6-b1 Qf4-g5 Qb1-g6+ Qg5xg6
29/58 00:08 30,740k 3,766k +0.10 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-e3 Qc5-f8 Re3-e7 Rg8-g6 Re7-e5 Qf8-d8 c4-c5 Qd8xf6+ Qf4xf6+ Rg6xf6 Re5-e4 Rf6-c6 Re4-c4 Kh8-g7 Kh4-g5 Kg7-f8 Kg5-f5 Kf8-e7 h3-h4 Rc6-h6 Rc4-e4+ Ke7-d7 Re4xa4 Rh6-h5+ Kf5-f6 Rh5xc5 Kf6xf7 Kd7-c6 Kf7-f6 Rc5-h5 Kf6-e6 Rh5-c5 Ra4-d4 Rc5-c3
30/65 00:08 31,474k 3,763k +0.09 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-e3 Qc5-f8 Re3-e7 Rg8-g6 Re7-e5 Qf8-d8 c4-c5 Qd8xf6+ Qf4xf6+ Rg6xf6 Re5-e4 Rf6-c6 Re4-c4 Kh8-g7 Kh4-g5 Kg7-f8 Kg5-f5 Kf8-e7 h3-h4 Rc6-h6 Rc4-e4+ Ke7-d7 Re4xa4 Rh6-h5+ Kf5-f6 Rh5xc5 Kf6xf7 Kd7-c6 Kf7-e6 Rc5-c3 Ra4-a7 h7-h5 Ra7-a4 Rc3-e3+ Ke6-f6
31/64 00:09 37,029k 3,731k +0.02 Re3-d3 a5-a4 c3-c4 Qc6-c5 Rd3-e3 Qc5-f8 Re3-c3 Qf8-c5 Rc3-g3 Rg8xg3 Qf4xg3 Qc5-d4+ Kh4-g5 h7-h6+ Kg5-f5 Qd4-c5+ Kf5-g4 Qc5-g5+ Kg4-f3 Qg5xf6+ Kf3-e4 Qf6-c6+ Ke4-d4 Qc6-d7+ Kd4-c5 Qd7-b7 Qg3-d3 Kh8-g7 h3-h4 h6-h5 Kc5-d4 Kg7-f6
32/65 00:11 41,782k 3,773k +0.02 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 a5-a4 h3-h4 Re6-e2 h4-h5 f7-f6 Rf5-d5 Kg7-f7 Kf4-f5 Re2-f2+ Kf5-e4 Rf2-c2 Ke4-d3 Rc2-c1 Kd3-d4 Kf7-e7 Rd5-f5 Ke7-e6 Rf5-f3 f6-f5 Rf3-e3+ Ke6-f6 Re3-e8 f5-f4 Kd4-d5 Rc1-d1+ Kd5-c6 Rd1-c1 Kc6-b5
33/54 00:13 49,189k 3,723k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 h3-h4 Rc1-c3 Kf4-e5 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-g8
34/59 00:13 50,440k 3,721k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 h3-h4 Rc1-c3 Kf4-e5 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-b8
35/60 00:14 53,584k 3,699k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 h3-h4 Rc1-c3 Kf4-e5 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-d8
36/66 00:15 55,497k 3,683k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 h3-h4 Rc1-c3 Kf4-e5 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 Ra7-c7
37/38 00:15 57,440k 3,654k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 Ra7-e7
38/41 00:16 58,684k 3,641k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 Ra7-a6
39/60 00:16 59,352k 3,638k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-b3
40/65 00:16 60,725k 3,635k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5
41/43 00:16 61,500k 3,633k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-b3
42/57 00:17 63,900k 3,633k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ra7-a6
43/69 00:17 65,285k 3,633k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+
44/64 00:19 71,544k 3,621k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+ Kd6-c5 Rd3-h3
45/73 00:22 81,157k 3,623k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+ Kd6-c5 Rd3-c3+
46/44 00:22 82,263k 3,619k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+ Kd6-e5
47/43 00:24 86,970k 3,598k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+
48/43 00:25 90,132k 3,589k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+
49/43 00:28 100,984k 3,553k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+
50/43 00:33 119,050k 3,514k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+
51/43 00:39 138,441k 3,466k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+
52/43 00:41 144,292k 3,452k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+
53/45 00:44 151,692k 3,436k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+ Kd6-c5 Rd3-h3
54/76 00:48 166,883k 3,419k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+ Kd6-c5 Rd3-h3
55/45 00:58 189,918k 3,220k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+
56/90 01:06 208,755k 3,142k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+ Kd6-c5 Rd3-h3 Ra7-a6 Kd8-c7 Ra6-a7+
57/47 01:12 222,517k 3,069k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+
58/43 01:15 232,580k 3,088k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+
59/45 01:21 256,401k 3,156k 0.00 c3-c4 Rg8-g6 Re3-g3 Qc6xf6+ Qf4xf6+ Rg6xf6 c4-c5 Rf6-c6 Rg3-g5 h7-h6 Rg5-f5 Kh8-g7 Kh4-g4 Rc6-e6 Kg4-f4 Re6-e1 Rf5-d5 Kg7-f6 c5-c6 Re1-c1 Rd5-d6+ Kf6-e7 Rd6xh6 a5-a4 Kf4-e5 Rc1-c3 h3-h4 Rc3xa3 Rh6-h8 Ra3-c3 Ke5-d5 a4-a3 Rh8-a8 f7-f5 Ra8-a7+ Ke7-d8 h4-h5 Rc3-d3+ Kd5-e5 Rd3-h3 Ke5-d6 Rh3-d3+ Kd6-c5 Rd3-h3
60/43+ 01:28 285,943k 3,219k +0.02 Re3-d3
60/43+ 01:29 286,739k 3,221k +0.03 Re3-d3
60/93+ 03:16 761,945k 3,878k +4.09 Re3-d3

[peter]

5.Qd4 indeed is a blind spot of most of the SF- branches I tried so far. SF dev needs MultiPV=6-8 to keep it in output till it starts climbing to first place, Crystal(9) is some faster with at least MultiPV=3. Internal MultiPV like the one of Cool Iris (Anton101) helped best in my trials with enough primaries set too. Here with Random Op. MultiPV=8, Random Op. Plies=29 and Random Op. Score=500, 30 threads of 16x4.3GHz CPU and 8G hash:

Code: Select all

 
4r2k/5p1p/1q3P2/p7/5Q2/P1P1R2P/5KP1/8 w - - 0 1

Analysis by Cool Iris 17:

5.c4 Txe3 6.Dxe3 Dxf6+ 7.Kg1 Kg8 8.c5 Kf8 9.Dc1 Dd4+ 10.Kh1 Ke7 11.c6 Kd8 12.Dg5+ Kc7 13.Dxa5+ Kxc6 14.Da6+ Kd7 
  Weiß steht besser.  
  +/- (1.07)  Tiefe: 10/29   00:00:00
5.a4 Txe3 6.Dxe3 Dxf6+ 7.Ke2 Kg8 8.Dd4 Dc6 9.Kd3 Dxg2 
  Weiß steht besser.  
  +/- (0.97)  Tiefe: 11/41   00:00:00
...
5.c4 Txe3 6.Dxe3 Dxf6+ 7.Kg1 Kg7 8.c5 Kf8 9.g4 a4 10.Kh2 Dc6 11.Kg3 f6 12.Dd4 Ke7 13.Kf4 Dc7+ 14.Ke4 Db7+ 15.Ke3 Db3+ 16.Dd3 Db2 17.Kf3 Kf7 18.Dxh7+ Kf8 19.Dd3 Dc1 20.Dd8+ 
  Weiß steht deutlich besser.  
  +/- (1.46)  Tiefe: 26/63   00:00:14  586MN, tb=1130295
5.Dd4 Db2+ 6.Kg3 Tc8 7.Dg4 Db8+ 8.Kh4 Tg8 9.De4 Df8 10.g4 Dh6+ 11.Kg3 Dxf6 12.Tf3 Dd6+ 13.Df4 De7 14.Te3 Df8 15.Df6+ Dg7 16.Dxg7+ Kxg7 17.c4 Tc8 18.Tc3 Tc5 19.Kf4 h5 20.gxh5 Kf6 21.h6 Tf5+ 22.Kg4 Tg5+ 23.Kh4 Tc5 24.h7 Kg7 25.Kg4 Kxh7 26.Kf4 Kg7 27.Ke4 Kf8 28.Kd4 Th5 29.Te3 Th4+ 30.Kd5 f5 31.c5 f4 32.Tf3a Ke8 33.Kc6 Kd8 34.Kb6 
  Weiß hat entscheidenden Vorteil.  
  +- (2.82)  Tiefe: 27/66   00:00:16  701MN, tb=1434539
...
5.Dd4 Db2+ 6.Kg3 Tc8 7.Dg4 Db8+ 8.Kh4 Tg8 9.De4 Df8 10.g4 Dh6+ 11.Kg3 Dxf6 12.Tf3 Dg7 13.c4 f6 14.De6 Tf8 15.c5 a4 16.Tf4 Tf7 17.Dd6 h6 18.Txa4 Dg5 19.Tf4 h5 20.Dd4 h4+ 21.Kg2 
  Weiß steht auf Gewinn.  
  +- (3.61)  Tiefe: 28/65   00:00:27  1176MN, tb=2852616
...
  +- (4.82)  Tiefe: 30/82   00:01:24  3480MN, tb=13196434
5.Dd4 Db2+ 6.Kg3 Tc8 7.Dg4 Db8+ 8.Kh4 Tg8 9.De4 Df8 10.g4 Dh6+ 11.Kg3 Dxf6 12.Tf3 Dg7 13.c4 f6 14.c5 a4 15.Dxa4 Tf8 16.Dd4 h6 17.a4 h5 18.Tf4 Df7 19.g5 Dg8 20.h4 Kh7 21.De4+ Kh8 22.Dc4 fxg5 23.Dxg8+ Txg8 24.Tc4 gxh4+ 25.Kxh4 Kg7 26.c6 Kf7 
  Weiß steht klar auf Gewinn.  
  +- (4.82)  Tiefe: 30/82   00:01:25  3508MN, tb=13325822

[jdart]

This is the output I get from Stockfish at 600 seconds/move, 8 threads, 16G hash on my workstation:

Code: Select all

6rk/5p1p/2q2P2/p7/5Q1K/P1P1R2P/8/8 w - - bm Qd4; c0 "posted by Uri Blass";

depth 48 seldepth 84 multipv 1 score PovScore(Cp(+547), WHITE) nodes 8322912347 nps 13871497 hashfull 522 tbhits 15347435 time 600.001 pv Rd3 Rc8 Rg3 Qd5 Qg5 Qe4+ Qg4 Qxg4+ Kxg4 h6 Kf5 h5 Ke4 h4 Rf3 Kh7 Kd5 Rd8+ Kc5 Kg6 c4 a4 Kb5 Rb8+ Kxa4 Ra8+ Kb3 Rb8+ Kc2 Rc8 Kc3 Kh7 Kb4 Rb8+ Ka5 Ra8+ Kb5 Rb8+ Ka6 Rc8 Rc3 Rg8 a4 Ra8+ Kb5 Rb8+ Kc6 Rc8+ Kb7 Rc5 Kb6 Rc8 c5 Rb8+ Ka6 Ra8+ Kb5
depth 48 seldepth 50 multipv 2 score PovScore(Cp(0), WHITE) nodes 8322912347 nps 13871497 hashfull 522 tbhits 15347435 time 600.001 pv c4 Rg6 c5 Rxf6 Qe5 Kg8 Qe8+ Qxe8 Rxe8+ Kg7 Ra8 Rf4+ Kg5 Rf3 Rxa5 Rxh3 a4 Rf3 Rb5 Ra3 a5 Kf8 c6 Ke7 Rc5 Kd8 c7+ Kc8 Kf4 Rd3 Ke4 Rd2 a6 Ra2 Rc6 Ra1 Ke5 Ra4 Kd5 Ra1
depth 48 seldepth 53 multipv 3 score PovScore(Cp(0), WHITE) nodes 8322912347 nps 13871497 hashfull 522 tbhits 15347435 time 600.001 pv Qd4 Rg6 Re4 Qxf6+ Qxf6+ Rxf6 Rc4 Kg7 Kg4 Rg6+ Kf3 Rh6 h4 Rh5 Kg3 Rd5 Rc6 a4 Rc4 Rd3+ Kg4 Kf6 Kf4 Rh3 Rc6+ Kg7 Kg4 Re3 Rc4 Rd3 Rc5 Rd1 Rg5+ Kh6 Ra5 Rc1 h5 Kg7 Ra6 h6 Rxa4 Rxc3 Kh4 Rc5 Rg4+ Kf6 Rb4
-- not solved (0 out of 1 solved, 0.0%)

This shows Rd3 with a winning score. Qd4 might be winning, also, but this analysis does not show that it is. Still, if there's another strong move, then this isn't a good test position.

[peter]

Your output is to position after 8th move of Uri's .pgn, Jon, mine was to the one after 4th move. 5.Qd4! also isn't the only winning move at this position, but it for sure is one of them and probably the fastest winning one compared to the next best candidates 5.a4(?!) and 5.c4(?!).

That's this one position after 4...Qb6
[d]4r2k/5p1p/1q3P2/p7/5Q2/P1P1R2P/5KP1/8 w - - 0 5
And it's the one, Uri's thread is about the blind spot, SF misevaluating 5.Qd4 as along as it doesn't have much hardware- time and or MultiPV- pondering and or Forward- Backward to positions like the one you (and him as for giving some output of follow- up- position there too) tried.
After 8....Qc6
[d]6rk/5p1p/2q2P2/p7/5Q1K/P1P1R2P/8/8 w - - 0 9