avoid ...a5

[pilgrimdan]

[d]r2q2kr/p2b1pb1/2p4p/4p1p1/1BN2p2/3Q4/PPP3PP/3R1RK1 b - - 0 20

[zullil]

[d]r2q2kr/p2b1pb1/2p4p/4p1p1/1BN2p2/3Q4/PPP3PP/3R1RK1 b - - 0 20

Stockfish (1 thread, 1024 MB hash) finally switches away for good at depth 31:

Code: Select all

info depth 31 seldepth 49 multipv 1 score cp -19 nodes 406188055 nps 1852059 time 219317 pv d8b8 d3d7 b8b4 d7c6 a8b8 d1d7 b4b5 c6b5 b8b5 b2b3 b5c5 f1e1 f7f5 c4e5 g7e5 b3b4 c5c7 d7c7 e5c7 e1e8 g8g7 e8e7 g7f6 e7c7 h8d8 a2a4 d8d1 g1f2 d1d2 f2f3 f6e5 c7e7 e5f6 e7a7 d2c2 a7h7 c2c3 f3f2 c3c2 f2f1

[zullil]

[d]r2q2kr/p2b1pb1/2p4p/4p1p1/1BN2p2/3Q4/PPP3PP/3R1RK1 b - - 0 20

Stockfish (1 thread, 1024 MB hash) finally switches away for good at depth 31:

Code: Select all

info depth 31 seldepth 49 multipv 1 score cp -19 nodes 406188055 nps 1852059 time 219317 pv d8b8 d3d7 b8b4 d7c6 a8b8 d1d7 b4b5 c6b5 b8b5 b2b3 b5c5 f1e1 f7f5 c4e5 g7e5 b3b4 c5c7 d7c7 e5c7 e1e8 g8g7 e8e7 g7f6 e7c7 h8d8 a2a4 d8d1 g1f2 d1d2 f2f3 f6e5 c7e7 e5f6 e7a7 d2c2 a7h7 c2c3 f3f2 c3c2 f2f1

Not for good. Back to a5 again:

Code: Select all

info depth 34 seldepth 54 multipv 1 score cp -29 nodes 1737965938 nps 1887017 time 921012 pv a7a5 b4a3 a8a7 f1e1 d8b8 a3d6 b8b5 a2a4 e5e4 a4b5 e4d3 b5b6 a7b7 d1d3 d7e6 e1e6 f7e6 d6c7 g7f8 c4a5 f8c5 g1f1 b7b6 d3d8 g8h7 c7b6 c5b6 d8h8 h7h8 a5c6 h8g7 c2c4 g7f6 b2b4 b6e3 f1e2 f6f5 e2d3 g5g4 b4b5 e3c5 g2g3

[zullil]

[d]r2q2kr/p2b1pb1/2p4p/4p1p1/1BN2p2/3Q4/PPP3PP/3R1RK1 b - - 0 20

A longer search with SF (16 threads, 8GB hash, MultiPV=3) suggests that both Rb8 and Qb8 are better than a5 (though the score for a5 doesn't seem very bad either).

Code: Select all

info depth 40 seldepth 61 multipv 1 score cp -7 nodes 18127915439 nps 16738981 time 1082976 pv a8b8 a2a3 b8b7 f1e1 a7a5 b4c5 d8b8 c4a5 b7c7 c5d6 b8a7 g1h1 d7g4 d6c7 g4d1 e1d1 a7c7 a5c4 c7c8 c4d6 c8d7 a3a4 f7f5 d6f5 d7d3 c2d3 g8f7 f5g7 f7g7 a4a5 h8a8 d1a1 g7f6 h1g1 g5g4 b2b4 f6e6 g1f2 e6d6 f2e2 h6h5 a1c1 h5h4 c1c5 a8b8 a5a6 b8b4

info depth 40 seldepth 61 multipv 2 score cp -13 nodes 18127915439 nps 16738981 time 1082976 pv d8b8 d3d7 b8b4 d7c6 a8b8 d1d7 b4b5 c6b5 b8b5 f1d1 b5c5 b2b3 a7a5 g1f1 g7f6 d1d5 c5d5 d7d5 a5a4 c4e5 f6e5 d5e5 g8g7 h2h4 a4b3 c2b3 g7f6 e5c5 g5g4 c5c4 f6f5 a2a4 h8a8 c4c5 f5e4 f1e2 a8e8 c5c4 e4f5 e2f2 e8e3 b3b4 e3a3 b4b5 a3a2 f2f1

info depth 40 seldepth 61 multipv 3 score cp -19 nodes 18127915439 nps 16738981 time 1082976 pv a7a5 b4a3 a8a7 f1e1 d8b8 a3d6 b8b5 a2a4 e5e4 a4b5 e4d3 b5b6 a7b7 d1d3 d7e6 e1e6 f7e6 d6c7 g7f8 c4a5 f8c5 g1f1 b7b6 d3d8 g8h7 d8h8 h7h8 c7b6 c5b6 a5c6 h8g7 b2b4 g7f6 c2c4 b6e3 f1e2 f6f5 e2d3 g5g4 c4c5 e3g1 c6d4 g1d4 d3d4 e6e5 d4d5 f4f3 g2f3 g4f3

[pilgrimdan]

here are the moves...

[Event ""]
[Site ""]
[Date "12-7-2014"]
[Round ""]
[White "6.55.90"] - Chessmaster 9000 setting (positional)
[Black "CM16"] - Chessmaster 9000 setting (default)
[Result "*"]

1. e4 e5
2. f4 exf4
3. Nf3 g5
4. Bc4 Nc6
5. O-O d6
6. d4 h6
7. Bd2 Bg7
8. Bc3 Bg4
9. Qd3 Nge7
10. Nbd2 Kf8
11. d5 Ne5
12. Nxe5 dxe5
13. Bb4 c6
14. Qb3 b5
15. d6 Nf5
16. exf5 bxc4
17. Nxc4 Bxf5
18. d7+ Kg8
19. Rad1 Bxd7
20. Qd3
[d]r2q2kr/p2b1pb1/2p4p/4p1p1/1BN2p2/3Q4/PPP3PP/3R1RK1 b - - 0 20
20. ...a5
21. Ba3 Ra7
22. Rfe1 f6
23. Bc5 Qb8
24. Bxa7 Qxa7+
25. Kh1 Be8
26. Qf5 Qc7
[d]4b1kr/2q3b1/2pR1p1p/4pQp1/p1N2p2/8/PPP3PP/4R2K w - - 0 28
here White chose Rd6... but Red1 seems to be a better move...
27. Rd6 a4
28. Rxf6 Bxf6
29. Qxf6 a3
30. Nxa3 Qg7
31. Qd6 Qd7
32. Qxe5 Bf7
33. Qc3 Kh7
34. Nc4 Bxc4
35. Qxc4 Re8
36. Qc3 Rxe1+
37. Qxe1 Qd5
38. h3 f3
39. gxf3 Qxf3+
40. Kh2 Qf4+
41. Kg2 Qc4
42. Qe7+ Kg6
43. Qe8+ Kf5
44. Qd7+ Ke5
45. Qg7+ Kf5
46. Qf8+ Ke5
47. Qe7+ Kf5
48. Qh7+ Ke5
49. Qh8+ Kf5
50. Qc3 Qxa2
51. b3 Qa6
52. Qf3+ Ke5
53. Qe3+ Kd6
*

[pilgrimdan]

[d]4b1kr/2q3b1/2pR1p1p/4pQp1/p1N2p2/8/PPP3PP/4R2K w - - 0 28
here White chose 28. Rxf6 but Red1 seems to be a better move...
28. Rxf6 Bxf6
29. Qxf6 a3
30. Nxa3 Qg7
31. Qd6 Qd7
32. Qxe5 Bf7
33. Qc3 Kh7
34. Nc4 Bxc4
35. Qxc4 Re8
36. Qc3 Rxe1+
37. Qxe1 Qd5
38. h3 f3
39. gxf3 Qxf3+
40. Kh2 Qf4+
41. Kg2 Qc4
42. Qe7+ Kg6
43. Qe8+ Kf5
44. Qd7+ Ke5
45. Qg7+ Kf5
46. Qf8+ Ke5
47. Qe7+ Kf5
48. Qh7+ Ke5
49. Qh8+ Kf5
50. Qc3 Qxa2
51. b3 Qa6
52. Qf3+ Ke5
53. Qe3+ Kd6
*

[yanquis1972]

the line you posted conflicts with SF at 22...f6?

[zullil]

the line you posted conflicts with SF at 22...f6?

Yes, Stockfish says 22...f6 loses the game for Black:

Code: Select all

+2.84 23. Bc5 Qb8 24. Bxa7 Qxa7+ 25. Kh1 Bg4 26. Qg6 Qe7 27. Rd2 Be6 28. Nd6 Bd5 29. c4 Qxd6 30. cxd5 h5 31. Rc1 c5 32. Rdc2 Rh6 33. Qe8+ Kh7 34. Rxc5 g4 35. Rb5 Qa6 36. Rc7 Rg6 37. Qc6 f5 38. Qxa6 Rxa6 39. Rbb7 Rg6 40. d6 Kh6 41. Rxg7 Rxd6 42. Rh7+ Kg5 43. Rbg7+ Kh4 44. Rd7 Rc6 45. Rc7 Rd6 46. Rhd7 Rxd7 47. Rxd7 f3 48. Kg1 (depth 40, 0:02:21)

[pilgrimdan]

[Event ""]
[Site ""]
[Date "12-7-2014"]
[Round ""]
[White "dani"]
[Black "CM16"]
[Result "*"]

1. e4 e5
2. f4 exf4
3. Nf3 g5
4. Bc4 Nc6
5. O-O d6
6. d4 h6
7. Bd2 Bg7
8. Bc3 Bg4
9. Qd3 Nge7
10. Nbd2 Kf8
11. d5 Ne5
12. Nxe5 dxe5
13. Bb4 c6
14. Qb3 b5
15. d6 Nf5
16. exf5 bxc4
17. Nxc4 Bxf5
18. d7+ Kg8
19. Rad1 Bxd7
20. Qd3 a5
21. Ba3 Ra7
22. Rfe1
[d]3q2kr/r2b1pb1/2p4p/p3p1p1/2N2p2/B2Q4/PPP3PP/3RR1K1 b - - 0 22
given more time Black switches from 22. ...f6 to 22. ...Qb8

Time Depth Score Positions Moves
0:03 1/9 0.20 1270665 22...f6 23.Bc5 Qb8 24.Bxa7 Qxa7+
25.Kh1 Be6 26.Nd6 Bg4 27.Rd2 Qb6
0:09 1/10 0.24 3324979 22...f6 23.Bc5 Qb8 24.Bxa7 Qxa7+
25.Kh1 Bg4 26.Rd2 Qc7 27.Qg6 h5
28.Qe8+ Kh7
0:27 1/11 0.26 9335620 22...f6 23.Bc5 Qb8 24.Kh1 Rc7 25.Nxa5
Bg4 26.Bd6 Bxd1 27.Rxd1 Qc8 28.Bxc7
Qxc7
0:58 1/12 0.42 20594256 22...f6 23.Bc5 Qb8 24.Bxa7 Qxa7+
25.Kh1 Bg4 26.Rd2 Qc7 27.Qc3 a4
28.Qa3 Bf8 29.Qxa4
3:08 1/13 0.67 67119247 22...f6 23.Bc5 Qb8 24.Bxa7 Qxa7+
25.Kh1 Bg4 26.Qg6 Bxd1 27.Rxd1
Qc7 28.Qf5 Qb8 29.Rd7 Qe8 30.Nxa5
c5 31.Qd3 e4
5:07 1/13 0.57 110473301 22...Qb8 23.Bd6 Qb5 24.a4 e4 25.Rxe4
Qf5 26.Be5 f6 27.Nd6 Qg6 28.Bd4
f5 29.Qc4+ Kh7 30.Bxa7 fxe4 31.Nxe4

[pilgrimdan]

the line you posted conflicts with SF at 22...f6?

Yes, Stockfish says 22...f6 loses the game for Black:

Code: Select all

+2.84 23. Bc5 Qb8 24. Bxa7 Qxa7+ 25. Kh1 Bg4 26. Qg6 Qe7 27. Rd2 Be6 28. Nd6 Bd5 29. c4 Qxd6 30. cxd5 h5 31. Rc1 c5 32. Rdc2 Rh6 33. Qe8+ Kh7 34. Rxc5 g4 35. Rb5 Qa6 36. Rc7 Rg6 37. Qc6 f5 38. Qxa6 Rxa6 39. Rbb7 Rg6 40. d6 Kh6 41. Rxg7 Rxd6 42. Rh7+ Kg5 43. Rbg7+ Kh4 44. Rd7 Rc6 45. Rc7 Rd6 46. Rhd7 Rxd7 47. Rxd7 f3 48. Kg1 (depth 40, 0:02:21)

[d]3q2kr/r2b1pb1/2p4p/p3p1p1/2N2p2/B2Q4/PPP3PP/3RR1K1 b - - 0 22
after 22. ...Qb8 (longer thinking time) here are the following moves... (instead of 22. ...f6)

23. Bd6 Qb5
24. a4 e4
25. Rxe4 Qd5
26. Qe2 Qf5
27. Bb8 Ra8
28. Be5 Be6
29. Nd6 Qg4
30. Qd3 Bd5
31. Bxg7 Kxg7
32. Re2 f3
33. Red2 Qf4
34. Nf5+ Kg8
35. Ne7+ Kg7
36. Nxd5 cxd5
37. Rf2 Rhf8
38. Rxf3 Qxa4
39. Qf5 Qc6
40. h4 gxh4
41. Rxd5 Qe6
42. Qd3 Qb6+
43. Kh2 Qb8+
44. Kh1 Qxb2
45. Rb5 Qa2
46. Rb6 Qa1+
47. Rf1 Qe5
48. Rb5 Qg3
49. Rf3 Qe1+
50. Rf1 Qe6
51. Qd4+ Kg8
52. Rf4 Kh7
*