Black to Play and Draw; Can any Engine See It?

[Spock]

A simple infinite analysis is probably not enough here, but anyway I tried that with a few engines. None find Qb6

Zappa Mexico II x64 4CPU (Intel Q6600)

12/40 0:00 +0.42 1...Bh4 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Be1 5.Qc6 Qc7 6.Qa8+ (919.056) 2033
12/40 0:00 +0.32 1...Kd8 2.Ka1 Be1 3.Qe2 Bg3 4.Qd2 Kc8 5.Nc3 Bh4 (1.261.712) 2075
12/40 0:00 +0.32 1...Kd8 2.Ka1 Be1 3.Qe2 Bg3 4.Qd2 Kc8 5.Nc3 Bh4 (1.575.117) 2102
13/40 0:00 +0.33 1...Kd8 2.Ka1 Be1 3.Qe2 Bg3 4.Nc3 Kc8 5.Qd2 Bh4 6.Kb2 (2.039.820) 2217
13/40 0:00 +0.33 1...Kd8 2.Ka1 Be1 3.Qe2 Bg3 4.Nc3 Kc8 5.Qd2 (2.189.348) 2227
14/40 0:01 +0.33 1...Kd8 2.Ka1 Be1 3.Kb1 Bg3 4.Ka2 Be1 5.Qe2 Bg3 6.Qd2 Bh2 7.Qd1 Bg3 8.Qe2 (2.995.387) 2313
14/46 0:01 +0.33 1...Kd8 2.Ka1 Be1 3.Kb1 Bg3 4.Ka2 Be1 5.Qe2 Bg3 6.Qd2 Bh2 7.Qd1 Bg3 8.Qe2 Ke7 9.Qd2 Kf8 10.Qd1 (3.227.885) 2299
15/46 0:02 +0.47 1...Kd8 2.Kb3 Kc8 3.Qd2 Kb7 4.Nc3 Bh4 5.Ka4 Kb6 6.Ne2 Qa8 7.Kb3 (6.182.940) 2388
15/49 0:04 +0.47 1...Kd8 2.Kb3 Kc8 3.Qd2 Kb7 4.Nc3 Bh4 5.Ka4 Kb6 6.Ne2 Qa8 7.Kb3 (11.776.413) 2435
16/49 0:05 +0.64 1...Kd8 2.Kb3 Kc8 3.Qd2 Kb7 4.Nc3 Bh2 5.Ka4 Qa8 6.Ne2 Kb6 7.Qc3 Qa7 (14.539.095) 2492
16/49 0:08 +0.56 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Bh2 5.Qf1 Bg3 6.Ka4 Kb6 7.Qe2 Bh2 8.Qf1 Qb7 9.Nd3 Qa8 (21.040.923) 2598
16/51 0:09 +0.56 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Bh2 5.Qf1 Bg3 6.Ka4 Kb6 7.Qe2 Bh2 8.Qf1 Qb7 9.Nd3 Qa8 (24.148.848) 2610
17/53 0:11 +0.67 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Bh2 5.Qf1 Bg3 6.Ka4 Kb6 7.Nd3 Qb8 8.Qe2 (29.554.772) 2638
17/53 0:15 +0.67 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Bh2 5.Qf1 Bg3 6.Ka4 Kb6 7.Nd3 Qb8 8.Qe2 (41.138.260) 2621
18/55 0:20 +0.67 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Bh2 5.Qe1 Bg3 6.Qd2 Bh2 7.Qd1 Bg3 8.Qd2 (52.226.706) 2589
18/55 0:23 +0.67 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Bh2 5.Qe1 Bg3 6.Qd2 Bh2 7.Qd1 Bg3 8.Qd2 (61.883.270) 2606
19/57 0:31 +0.69 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Bh2 5.Qe1 Bg3 6.Qd2 Bh2 7.Qe1 (83.249.196) 2664
19/57 0:46 +0.69 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Bh2 5.Qe1 Bg3 6.Qd2 Qa8 7.Qe2 Qb8 8.Qd2 (122.736.505) 2624
20/59 1:02 +0.70 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Bh2 5.Ka4 Qa8 6.Qd1 Kb6 7.Nd3 Bg3 8.Qc2 Bh2 9.Qb1 Qa7 (167.038.603) 2655
20/59 1:22 +0.70 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Bh2 5.Ka4 Qa8 6.Qd1 Kb6 7.Nd3 Bg3 8.Qc2 Bh2 9.Qb1 Qa7 (220.530.578) 2670
21/61 2:12 +0.84 1...Be1 2.Qe2 Bg3 3.Nc3 Qa8 4.Kb3 Bh2 5.Ka4 Bg1 6.Nb1 Bd4 7.Nd2 Kd7 8.Nb3 Bc3 9.Qc2 Bd4 10.Qd2 (360.790.520) 2716
21/61 3:50 +0.84 1...Be1 2.Qe2 Bg3 3.Nc3 Qa8 4.Kb3 Bh2 5.Ka4 Bg1 6.Nb1 Bd4 7.Nd2 Kd7 8.Nb3 Bc3 9.Qc2 Bd4 10.Qd2 (619.723.482) 2690
22/63 5:09 +0.86 1...Be1 2.Qe2 Bg3 3.Kb3 Qa8 4.Nc3 Bh2 5.Ka4 Bg1 6.Nb1 Bd4 7.Nd2 Kd7 8.Nb3 Bc3 9.Qc2 Be1 10.Qc1 Bf2 (841.769.865) 2717
22/63 7:38 +0.86 1...Be1 2.Qe2 Bg3 3.Kb3 Qa8 4.Nc3 Bh2 5.Ka4 Bg1 6.Nb1 Bd4 7.Nd2 Kd7 8.Nb3 Bc3 9.Qc2 Be1 10.Qc1 Bf2 (1.219.202.296) 2656
23/65 9:31 +0.87 1...Be1 2.Qe2 Bg3 3.Kb3 Qa8 4.Nc3 Bh2 5.Qf1 Kb7 6.Ka4 Qg8 7.Qd1 Bg3 8.Nb1 Bf2 9.Nd2 Qa8 10.Nb3 Kc8 11.Qe2 (1.503.553.739) 2630
23/65 13:40 +0.87 1...Be1 2.Qe2 Bg3 3.Kb3 Qa8 4.Nc3 Bh2 5.Qf1 Kb7 6.Ka4 Qg8 7.Qd1 Bg3 8.Nb1 Bf2 9.Nd2 Qa8 10.Nb3 Kc8 11.Qe2 (2.137.911.441) 2604
24/67 17:00 +0.87 1...Be1 2.Qe2 Bg3 3.Kb3 Qa8 4.Nc3 Bh2 5.Qf1 Kb7 6.Ka4 Qg8 7.Qd1 Bg3 8.Nb1 Bf2 9.Nd2 Qa8 10.Nb3 Kc8 11.Qe2 Bd4 12.Qe1 Kb7 13.Nxa5+ (2.616.403.843) 2562
24/67 22:10 +0.87 1...Be1 2.Qe2 Bg3 3.Kb3 Qa8 4.Nc3 Bh2 5.Qf1 Kb7 6.Ka4 Qg8 7.Qd1 Bg3 8.Nb1 Bf2 9.Nd2 Qa8 10.Nb3 Kc8 11.Qe2 Bd4 12.Qe1 Kb7 13.Nxa5+ (3.376.874.801) 2538
25/69 56:45 +0.88 1...Be1 2.Qe2 Bg3 3.Kb3 Qa8 4.Nc3 Bh2 5.Qf1 Kb7 6.Ka4 Qg8 7.Qd1 Bg3 8.Nb1 Bf2 9.Nd2 Qa8 10.Nb3 Qa7 11.Qd2 Be3 12.Qe1 (4.906.909.171) 1441
25/69 111:32 +0.88 1...Be1 2.Qe2 Bg3 3.Kb3 Qa8 4.Nc3 Bh2 5.Qf1 Kb7 6.Ka4 Qg8 7.Qd1 Bg3 8.Nb1 Bf2 9.Nd2 Qa8 10.Nb3 Qa7 11.Qd2 Be3 12.Qe1 (7.071.442.142) 1056
26/71 246:01 +0.97 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qc7 6.Kb1 Ke7 7.Kc1 Bf2 8.Kc2 Kd8 9.Qa6 Bd4 10.Nb6 Qb8 11.Qb5 Qc7 12.Qa6 (12.143.419.130) 822
26/71 314:21 +0.97 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qc7 6.Kb1 Ke7 7.Kc1 Bf2 8.Kc2 Kd8 9.Qa6 Bd4 10.Nb6 Qb8 11.Qb5 Qc7 12.Qa6 (14.913.152.327) 790
27/73 477:28 +0.97 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qc7 6.Qa6 Qb8 7.Qc6 Qc7 8.Qb5 Qc8 (20.981.903.061) 732
27/73 534:50 +0.97 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qc7 6.Qa6 Qb8 7.Qc6 Qc7 8.Qb5 Qc8 9.Kb3 Qc7 10.Qa6 h4 11.Ka2 Qb8 12.Qb5 Qa7 13.Kb2 Ke7 14.Nb6 Qc7 (23.365.359.119) 728
28/75 986:46 +1.06 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qc7 6.Kb3 Qa7 7.Kc2 Qc7 8.Kd1 Bf2 9.Nb6 Qb7 (40.297.537.756) 680
28/75 1603:20 +1.06 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qc7 6.Kb3 Qa7 7.Kc2 Qc7 8.Kd1 Bf2 9.Nb6 Qb7 (63.684.504.184) 661
best move: Bg3-e1 time: 1625:38.564 min n/s: 890.335 nodes: 64.566.482.175


2k5/q1p5/3p4/pPpPp1pp/N1P1Pp2/P4PbP/KQ4P1/8 b - - 0 45

Rybka 3 x64 1 CPU (Intel QX6700)


12.00 0:00 +0.31 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Qb8 5.Qd2 Qa8 6.Ka4 (60.261) 77
13.01 0:01 +0.31 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Qb8 5.Qd2 Qa8 6.Ka4 (92.608) 76
14.01 0:01 +0.31 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Qb8 5.Qd2 Qa8 6.Ka4 Kb6 (126.579) 78
15.01 0:02 +0.31 1...Be1 2.Kb3 Kb7 3.Qe2 Bg3 4.Nb2 Qa8 5.Qd2 Kb6 6.Ka4 Bh2 7.Qe1 (183.777) 78
16.01 0:04 +0.34 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Nb6 Qb7 8.Kc2 (321.501) 77
17.01 0:07 +0.34 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Nb6 Qb7 8.Kc2 (601.695) 78
18.01 0:12 +0.34 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Nb6 Qb7 8.Kc2 (953.237) 80
19.01 0:18 +0.34 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Nb6 Qb7 8.Kc2 (1.425.411) 80
20.01 0:27 +0.35 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Kc2 Qa7 8.Kd3 Bf2 9.Qc6 Qd7 10.Qa8+ (2.183.281) 80
21.01 0:47 +0.36 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Kc2 Qa7 8.Kd3 Bf2 9.Qc6 Qd7 10.Qa8+ Ke7 (3.681.709) 78
22.01 1:22 +0.48 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Kc2 Ke7 8.Kd3 Bf2 9.Qa6 Bd4 10.Nb6 a4 11.Nxa4 (6.244.877) 77
23.01 2:31 +0.48 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Kc2 Ke7 8.Kd3 Bf2 9.Qa6 Qb8 10.Nb6 Be1 11.Kc2 (11.360.514) 76
24.01 4:37 +0.66 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Kc2 Ke7 8.Kd3 Kd8 9.Ke2 (20.615.109) 76
25.01 27:49 +0.86 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Kc2 h4 8.Kd1 Bf2 9.Nb6 Be3 10.Qxa5 Qb7 11.Kc2 Bd4 12.Na4+ (120.354.470) 73
26.01 31:59 +0.86 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Kc2 h4 8.Kd1 Bf2 9.Nb6 Be3 10.Qxa5 Qb7 11.Kc2 Bd4 12.Na4+ (141.881.589) 75
27.01 53:15 +0.86 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Kc2 h4 8.Kd1 Bf2 9.Nb6 Qb7 10.Qxa5 Be3 11.Kc2 (240.724.269) 77
28.01 94:44 +0.86 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Kc2 h4 8.Kd1 Bf2 9.Nb6 Qb7 10.Qxa5 Be3 11.Kc2 (441.505.911) 79
29.01 133:17 +0.86 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Kc2 h4 8.Kd1 Bf2 9.Nb6 Qb7 10.Qxa5 Be3 11.Kc2 (620.244.926) 79
30.01 235:06 +0.86 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 Qa7 6.Kb3 Qc7 7.Kc2 h4 8.Kd1 Bf2 9.Nb6 Qb7 10.Qxa5 Be3 11.Kc2 (1.118.001.499) 81
31.01 1092:40 +1.19 1...Be1 2.b6 cxb6 3.Qb5 Kd8 4.Nxb6 Qb7 5.Na4 (5.103.062.220) 79 TB:4
best move: Bg3-e1 time: 1221:39.566 min n/s: 79.346 nodes: 5.679.668.662 TB: 5


Deep Shredder 11 x64 4CPU (slow-ish Quad Core Operon 1352)

15/25 0:01 +1.06 1...Bh2 2.Qc1 Qa8 3.Kb3 Bg3 4.Qd2 Kb7 5.Nb2 Kb6 6.Qd1 h4 7.Na4+ Kb7 8.Qd2 (3.067.830) 2427
16/41 0:02 +0.97 1...Bh2 2.Qc1 Qa8 3.Kb3 Bg3 4.Qd2 Kb7 5.Nb2 Kb6 6.Qd1 h4 7.Qe2 Bh2 8.Qe1 Kb7 (5.530.133) 2530
17/37 0:02 +0.97 1...Bh2 2.Qc1 Qa8 3.Kb3 Bg3 4.Qd2 Kb7 5.Nb2 Kb6 6.Ka2 h4 7.Kb3 Bh2 8.Qe1 Kb7 (6.484.750) 2565
18/35 0:02 +0.97 1...Bh2 2.Qc1 Qa8 3.Kb3 Bg3 4.Qd2 Kb7 5.Nb2 Kb6 6.Ka2 h4 7.Kb3 Bh2 8.Qe1 Kb7 (7.454.025) 2596
19/49 0:10 +1.21 1...Bh2 2.Qc1 (28.858.317) 2688 SB:4
20/50 0:30 +1.45 1...Bh2 2.Qc1 (86.225.842) 2828 SB:24
21/55 1:42 +1.52 1...Bh2 2.b6 Qa6 3.Qb5 Qxb5 4.cxb5 Bg1 5.bxc7 Kxc7 6.Nb2 Bd4 7.Nc4 a4 8.b6+ Kb7 9.Kb1 Bc3 10.Kc2 Bd4 11.Nxd6+ Kxb6 12.Nf7 Kc7 13.Nxg5 Kd6 14.Ne6 h4 (304.734.970) 2979

SB:40
21/55 2:02 +1.49 1...Kd7 2.Kb3 Bh2 3.Qd2 Qa8 4.Nc3 Bg1 5.Ka4 Be3 6.Qe1 Qg8 7.Nd1 Bd4 8.Qxa5 Qc8 9.Qa6 Qb8 10.Qc6+ Ke7 11.Kb3 Qa7 12.Qa6 Qb8 (365.611.252) 2983 SB:40
22/45 2:36 +1.48 1...Kd7 2.Kb3 Bh2 3.Qd2 Qa8 4.Nc3 Bg1 5.Ka4 Be3 6.Qe1 Qd8 7.Nd1 Bd4 8.Qxa5 Ke7 9.Qa6 g4 10.hxg4 hxg4 11.Kb3 g3 12.Qc6 Qb8 13.a4 Qa7 14.Qa6 Qb8 (468.504.773) 2992

SB:47
23/50 3:22 +1.49 1...Kd7 2.Kb3 Bh2 3.Qd2 Qa8 4.Nc3 Bg3 5.Ka4 g4 6.fxg4 hxg4 7.hxg4 Qh8 8.Na2 Qh1 9.Qc2 Ke7 10.Kxa5 Bh4 11.Ka6 Be1 12.Kb7 Kd7 13.a4 Qh8 14.Nc3 Qc8+ (601.857.989) 2978

SB:120
24/58 18:28 +1.70 1...Kd7 2.Kb3 Bh2 3.Qd2 Qa8 4.Nb2 Bg1 5.Ka4 Kc8 6.Qxa5 Qxa5+ 7.Kxa5 Bd4 8.Nd3 Kb7 9.Ka4 h4 10.Nc1 Kb6 11.Ne2 Be3 (3.558.467.379) 3210 SB:3.449
25/52 29:35 +1.70 1...Kd7 2.Kb3 Bh2 3.Qd2 Qa8 4.Nb2 Bg1 5.Ka4 Kc8 6.Qxa5 Qxa5+ 7.Kxa5 Bd4 8.Nd3 Kb7 9.Ka4 h4 10.Nc1 Kb6 11.Ne2 Be3 (5.713.008.892) 3217 SB:12.798
26/60 38:14 +1.68 1...Kd7 2.Kb3 Bh2 3.Qd2 Qa8 4.Nb2 Bg1 5.Ka4 Kc8 6.Qxa5 Qxa5+ 7.Kxa5 Bd4 8.Nd3 Kb7 9.Ka4 h4 10.Nc1 Kb6 11.Ne2 Be3 (7.501.482.538) 3269 SB:16.245
27/62 67:29 +1.67 1...Kd7 2.Kb3 Bh2 3.Qd2 Qa8 4.Nb2 Bg1 5.Ka4 Kc8 6.Qxa5 Qxa5+ 7.Kxa5 Bd4 8.Nd3 Kb7 9.Ka4 h4 10.Nc1 Kb6 11.Ne2 Be3 12.Kb3 Bd2 13.Nc3 Ka5 14.Nd1 Be3 (14.017.409.856) 3461

SB:23.725
28/64 137:35 +1.65 1...Kd7 2.Kb3 Bh2 3.Qd2 Qa8 4.Nb2 Bg1 5.Ka4 Kc8 6.Qxa5 Qxa5+ 7.Kxa5 Bd4 8.Nd3 Kb7 9.Ka4 h4 10.Nc1 Kb6 11.Ne2 Be3 12.Kb3 Bd2 13.Nc3 Ka5 14.Nd1 Be3 (30.067.587.484) 3642

SB:43.861
29/62 158:14 +1.65 1...Kd7 2.Kb3 Bh2 3.Qd2 Qa8 4.Nb2 Bg1 5.Ka4 Kc8 6.Qxa5 Qxa5+ 7.Kxa5 Bd4 8.Nd3 Kb7 9.Ka4 h4 10.Nc1 Kb6 11.Ne2 Be3 12.Kb3 Bd2 13.Nc3 Ka5 14.Nd1 Be3 (34.348.015.978) 3617

SB:74.043
30/73 803:08 +1.60 1...Kd7 2.Kb3 Kc8 3.Qd2 Bh2 4.Nc3 Bg1 5.Ka4 Kb7 6.Ne2 Bd4 7.Qxa5 Qxa5+ 8.Kxa5 h4 9.Ka4 Kb6 10.Kb3 Ka5 11.Nc3 Bf2 12.Nd1 Be1 13.Nb2 Bd2 14.Na4 Be1 (175.901.983.661)

3650 SB:1.243.843
best move: Kc8-d7 time: 804:18.410 min n/s: 3.650.306 CPU 399.4% n/s(1CPU): 913.947 nodes: 176.157.844.124 SB: 1.244.547

[GenoM]

How are you playing after
1...Qb6 2.Qe2 Bh4 3. Nxb6+ cxb6
or
1...Qb6 2.Qe2 Bh4 3. g3 fxg3 ?

Ignore my last post please .. looks obvious now.

1. Nxb6+ cxb6 2. g3 Bxg3 (2... fxg3 3. f4 gxf4 4. Qxh5) 3. h4 gxh4 (3... Bxh4 4. Qg2 Kb7 5. Qh3) 4. Qg2 Kb7 5. Qh3

Well, then
[d]2k5/q1p5/3p4/pPpPp1pp/N1P1Pp2/P4PbP/KQ4P1/8 b - - 0 45
after 1...Qb6 2.Qe2 --2... Kb7
What is your variation?
If 3.Kb3 (as in your previous post) then just 3...Qa7 4.Nc3 a4+
5.Nxa4 Qa5 6.Nc3 Kc8 7.Qd2 (7.Qc2 with idea of Nc3-e2 -- but then 7...Be1 and white can not break through) 7...Kb7 8.Nb1 Qa7 9.a4 Kb6 10.Ka3 Qa5 11.Qxa5+ Kxa5 12.Nd2 Be1 13.Nb3+ Kb6 14.Kb2 Bb4 15.Kc2 Be1 16.Kd3 Bb4 17.Ke2 Bc3 18.Kf2 h4 19.Ke2 Bb4 20.Kd3 Ba5 21.Kc2 Be1 22.Nc1 Bf2 23.Nb3 Be1 24.Nc1 Bf2 25.Nd3 Bd4 26.Kb3 Ka5 27.Nc1 Be3

Yesterday evening, Pradu, Salva and I continued the analysis and already found the threat of a4+! So we decided that Qd2 should be superior. Anyway the position seems to be a draw after all, as white can make no progress in certain lines.

even not playing Qb6 is a good option. Sooner or later Queens will be traded and the Knight has not enough squares to force any of the queenside pawns to be pushed forward. Furthermore the Bishop can come from behind and trap the Knight easily.

a4+ is important because jeopardizes white chances to penetrate with the King.

White needs to force black to play h4 with, for instance 1... Qb6 2. Qb1! h4 (otherwise, white takes the queen and plays h4 gxh4/ Qh1 winning).

Once black plays h4, an entrance for the Knight is created in g4 through f2 or f1-h2. Black will have to protect those squares with the bishop, which won't allow it to protect a5 simultaneously. So, if white trades queen with the white pawn in a3 (CRITICAL! so the king can go a4-a5) white wins. Blacks chances are good if it AVOIDS trading queens until white plays a4.

Black should play place pieces at Kb7 & Qa7 and possibly wait with Qa7-Qa8 until white plays a4 and then play Kb6-Qa5.

This may be a draw but black need to be very careful in its maneuvers.

Miguel

Miguel, talk with variations please. It's a draw.

Regards,
Geno

[michiguel]

How are you playing after
1...Qb6 2.Qe2 Bh4 3. Nxb6+ cxb6
or
1...Qb6 2.Qe2 Bh4 3. g3 fxg3 ?

Ignore my last post please .. looks obvious now.

1. Nxb6+ cxb6 2. g3 Bxg3 (2... fxg3 3. f4 gxf4 4. Qxh5) 3. h4 gxh4 (3... Bxh4 4. Qg2 Kb7 5. Qh3) 4. Qg2 Kb7 5. Qh3

Well, then
[d]2k5/q1p5/3p4/pPpPp1pp/N1P1Pp2/P4PbP/KQ4P1/8 b - - 0 45
after 1...Qb6 2.Qe2 --2... Kb7
What is your variation?
If 3.Kb3 (as in your previous post) then just 3...Qa7 4.Nc3 a4+
5.Nxa4 Qa5 6.Nc3 Kc8 7.Qd2 (7.Qc2 with idea of Nc3-e2 -- but then 7...Be1 and white can not break through) 7...Kb7 8.Nb1 Qa7 9.a4 Kb6 10.Ka3 Qa5 11.Qxa5+ Kxa5 12.Nd2 Be1 13.Nb3+ Kb6 14.Kb2 Bb4 15.Kc2 Be1 16.Kd3 Bb4 17.Ke2 Bc3 18.Kf2 h4 19.Ke2 Bb4 20.Kd3 Ba5 21.Kc2 Be1 22.Nc1 Bf2 23.Nb3 Be1 24.Nc1 Bf2 25.Nd3 Bd4 26.Kb3 Ka5 27.Nc1 Be3

Yesterday evening, Pradu, Salva and I continued the analysis and already found the threat of a4+! So we decided that Qd2 should be superior. Anyway the position seems to be a draw after all, as white can make no progress in certain lines.

even not playing Qb6 is a good option. Sooner or later Queens will be traded and the Knight has not enough squares to force any of the queenside pawns to be pushed forward. Furthermore the Bishop can come from behind and trap the Knight easily.

a4+ is important because jeopardizes white chances to penetrate with the King.

White needs to force black to play h4 with, for instance 1... Qb6 2. Qb1! h4 (otherwise, white takes the queen and plays h4 gxh4/ Qh1 winning).

Once black plays h4, an entrance for the Knight is created in g4 through f2 or f1-h2. Black will have to protect those squares with the bishop, which won't allow it to protect a5 simultaneously. So, if white trades queen with the white pawn in a3 (CRITICAL! so the king can go a4-a5) white wins. Blacks chances are good if it AVOIDS trading queens until white plays a4.

Black should play place pieces at Kb7 & Qa7 and possibly wait with Qa7-Qa8 until white plays a4 and then play Kb6-Qa5.

This may be a draw but black need to be very careful in its maneuvers.

Miguel

Miguel, talk with variations please. It's a draw.

Regards,
Geno

I am not ready to rush to say it is a draw, but it may be. Black has some problems to resolve. Before shuffling pieces back and forth, we should try to analyze this type of endgames with plans rather than variations (that is why certain endgames like this are not computer's forte). That is why I explained my ideas. A full blown analysis may turn very dense without a clear plan.

Just an illustration of lines that black should avoid:

45...Qb6 46.Qb1 h4 47.Qf1 Kb8 48.Kb3 Qa7 49.Nc3 a4+ 50.Kc2 (white will try to capture in a more favorable situation keeping the bishop out of play) Qa5 51.Kd3 Kb7
52.Qe2 Bh2 53.Qd1 Bg3 54.Qc2 Bh2 55.Qxa4 Kb6
( 55...Qxa4 56.Nxa4 Bg3 57.b6 )
56.Qxa5+ Kxa5 57.b6
and Black has some problems. White will place the Nb5, a4-a5-a6 Black will take Kxa6 and Nxc7+ will give white a nice advantage. If Black tries to come back with the bishop with Bg3, white plays Ke2

Miguel