MikeGL wrote: ↑Thu May 09, 2019 3:23 am
Complete game with your Nf1 possibility inserted at move 35 and black still has positional dominance to compensate for the exchange sac:
[pgn]
[Event "?"]
[Site "?"]
[Date "????.??.??"]
[Round "?"]
[White "Stockfish 10 181129"]
[Black "Lc0 0.21.1 N:42100"]
[Result "0-1"]
[TimeControl "5400+5"]
[SetUp "1"]
[FEN "rn1qkbnr/ppp2ppp/8/3p1b2/3P4/5N2/PP2PPPP/RNBQKB1R w KQkq - 0 1"]
[Termination "normal"]
[PlyCount "141"]
[WhiteType "human"]
[BlackType "human"]
1. Qb3 Nc6 2. Bg5 f6 3. Bd2 Qd7 4. Nc3 O-O-O 5. Na4 Bd6 6. e3 Nge7 7. a3 h5
8. Bb4 Kb8 9. Bxd6 cxd6 10. Nc3 h4 11. Nd2 Qe6 12. Ba6 Na5 13. Qb5 Rd7 14.
Qxa5 bxa6 15. Qxa6 h3 16. g3 Rb7 17. Ra2 g5 18. O-O Rc8 19. Re1 Bg6 20. Qf1
Nc6 21. Raa1 Ka8 22. Ra2 Kb8 23. f3 Na5 24. Qf2 f5 25. f4 g4 26. Qe2 Be8
27. Kf2 Rxc3 28. bxc3 Bb5 29. Qd1 Bc4 30. Rc2 Bd3 31. Ra2 Nc4 32. Qa1 Kc7
33. Kg1 a5 34. Qd1 Nb2 35. Qc1 (35. Qa1 Na4 36. Nf1 Bxf1 37. Kxf1 Qe4 38.
Kg1 Rb3) 35. .. Na4 36. Qd1 Qe8 37. Nf1 Qb5 38. Rf2 Nb2 39. Qa1 a4 40. Rc1
Nc4 41. Rd1 Bxf1 42. Rdxf1 Qe8 43. Qd1 Rb3 44. Qc2 Qe4 45. Ra1 Kc6 46. Re2
Kb6 47. Qc1 Kb5 48. Rf2 Qd3 49. Qc2 Qxc3 50. Qxc3 Rxc3 51. Rfa2 Nxe3 52.
Rb2+ Rb3 53. Rd2 Nc4 54. Rda2 Nb2 55. Rc1 Nd3 56. Rd1 Rc3 57. Re2 Kc4 58.
Re7 Rxa3 59. Rc7+ Kxd4 60. Rc2 Rc3 61. Ra2 a3 62. Rda1 Ke4 63. Rxa3 d4 64.
Ra6 Kd5 65. R6a2 Nc5 66. Kf2 Rb3 67. Ke2 Ke4 68. Kf2 d3 69. Ra4+ Nxa4 70.
Rxa4+ Kd5 71. Ke3 0-1
[/pgn]
The line you give after 35.Qa1 Na4 36.Nf1
(
35. Qa1 Na4 36. Nf1 Bxf1 37. Kxf1 Qe4 38. Kg1 Rb3
)
is only 5 plies long, Mike, after those I have this:
[d]8/2k5/3p4/p2p1p2/n2PqPp1/PrP1P1Pp/R6P/Q3R1K1 w - - 0 1
Analysis by Cfish 060519 64 POPCNT NUMA:
39.Tf2 Sxc3 40.a4 Kd7 41.Dc1 Sxa4 42.Da1 Tb4 43.Da3 Ke6 44.Td1 Kf7 45.Te1 Kf6 46.Dc1 Tc4 47.Dd2 Sc3 48.Tc1 Sb5 49.Txc4 dxc4 50.Dxa5 Db1+ 51.Tf1 Dc2 52.Dd8+ Kf7 53.Dd7+ Kf8 54.Dc8+ Ke7 55.Db7+ Ke6 56.Dc8+ Kf7
= (0.00) Tiefe: 60/36 00:06:50 10444MN
How does Black continue to take advantage of its "positional dominance"? It can get the white a- and c- Pawn, but then the free black a-Pawn doesn't make it against White's quality of Rook against Night. Not as far as I can see. In best or worst case, depending from which side you look at it, White can give back quality in exchange against this remaining pawn at a- line. So what?
And then there are still the Queens on board, which gives White a second one chance to come into Black's back- ranks chasing King into checks repeated, as seen in output- line above, after Black exchanged Rooks and gave a- Pawn against setting free the one on c-line.
In the game after 35.Dc1(?), which might well be the latest game changing blunder, some other suboptimal moves followed up like 38.Rf2(?), even here Qa1 instead would have given better resistance still, making the real dominance by Black at this point then decisive in a hopeless way from White's side. Yet at this point (38.ff) White's already in Zugzwang, which is the real reason for SF not to see the danger coming sooner and better.
But up to this 35th move of White, the position is equal. White can build up a fortress, if it doesn't miss the chance for it.
What output and eval does LC0 show there at your hardware?
I have only weak installation of Leela, so better try out with yours, if you'd like to have some playout from there onwards, I'll be glad to check your LC0- lines with SF at my hardware with CPU much stronger then GPU.
27...Rxc3 is a good and a beautiful move, but after all, it's just setting up a trap. So I wouldn't call it a game changing single one best move.
Peter.