Great surprise: balanced openings can still be won

[CornfedForever]

Fisher played many things to avoid theory, he also played f4, Kf2, Kf3. doesn't mean anything.

He also played The Benoni. Nuff said.

[Kanizsa]

Fisher played many things to avoid theory, he also played f4, Kf2, Kf3. doesn't mean anything.

it has never been proven, certainly just a joke by Nigel Short

[Ozymandias]

Some sense of humor, saying someone clobbered you 8-0.

[Ajedrecista]

Hello:

It's like the oldest way to meet Bb5. Long ago superseded.

[...]

3.- ..., Bc5 —Classical Defence— appears in the Ruy López's book of 1561. The first chapter to cover a Ruy López opening —Chapter IX— says 3.- ..., d6; 4.- Bxc6+, bxc6; 5.- d4 (link). The next chapter starts to cover 3.- ..., Bc5:

https://bdh-rd.bne.es/viewer.vm?id=0000122820&page=235

Code: Select all

Chapter X → 1.- e4, e5; 2.- Nf3, Nc6; 3.- Bb5, Bc5; 4.- Bxc6, dxc6; 5.- Nxe5, Bxf2+; 6.- Kxf2, Qd4+; 7.- ~, Qxd4 (-+)
            1.- e4, e5; 2.- Nf3, Nc6; 3.- Bb5, Bc5; 4.- Bxc6, dxc6; 5.- Nxe5, Qd4; 6.- Ng4, Qxe4+; 7.- Ne3, Bxe3; 8.- dxe3, Qxg2; 9.- Rf1, Bh3 (-+)
            1.- e4, e5; 2.- Nf3, Nc6; 3.- Bb5, Bc5; 4.- Bxc6, dxc6; 5.- Nxe5, Qd4; 6.- Ng4, Qxe4+; 7.- Ne3, Bxe3; 8.- fxe3, Qxg2; 9.- Rf1, Bg4 (-+)
            1.- e4, e5; 2.- Nf3, Nc6; 3.- Bb5, Bc5; 4.- Bxc6, dxc6; 5.- Nxe5, Qd4; 6.- Nd3, Qxe4+; 7.- Qe2; Qxe2+; 8.- Kxe2, Bb6; 9.- c4, Bf5 (10.- c5, Bxd3+; 11.- Kxd3, Bxc5)

More lines in Chapter X and following chapters.

I hope no typos.

The Classical Defence is covered by ECO C64. 3.- ..., Bc5; 4.- c3, Nf6; 5.- O-O transposes to ECO C65 according to the Fifth Edition (2006) of the Volume C of the Encyclopedia of Chess Openings (note 19 at ECO C64). Then, note 96 at ECO C65 enters into 7.- a4!?, a6; 8.- Bxc6, dxc6; 9.- Nxe5, Nxe4; 10.- a5, Ba7; 11.- Re1, Nd6 (transposition of moves 10 and 11 from the game of this thread). Then, Beliavsky gives 12.- Bf4± (deviating from 12.- Be3 of this thread). This sample game from ECO is Beliavsky 1—0 Sepp (Pärnu, 1997), which featured 12.- b4.

Regards from Spain.

Ajedrecista.

[lkaufman]

Can the strongest engines still win by playing each other from super balanced opening lines?

In the main engine competitions, like CCC and TCEC, we are getting used to the idea that in order to strike blood on the chessboard, the initial imbalance should be at least of the order of a pawn or so

(* 0,70 according to Larry Kaufman, at least 1.00 according to Jeroen Noomen).

To our surprise, this incredible victory of Leela against SF comes from TCEC.

Just a 3-move opening line,

1. e4 e5 2. Nf3 Nc6 3. Bb5 Bc5

with both engines evaluating it only +0,26;

[Event "TCEC Season 24 - Kibitzer Bonus"]
[Site "https://tcec-chess.com"]
[Date "2023.05.04"]
[Round "12.1"]
[White "LCZero dag-master-pr1821-1842e13-T1-3905000"]
[Black "Stockfish master-72d542f"]
[Result "1-0"]
[Annotator "archive"]

[pgn]
1. e4 e5 2. Nf3 Nc6 3. Bb5 Bc5 4. c3 Nf6 5. O-O O-O 6. d4 Bb6 7. a4 a6 8. Bxc6 dxc6 9. Nxe5 Nxe4 10. Re1 Nd6 11. a5 Ba7 12. Be3 Be6 13. Nf3 f6 14. b4 Nb5 15. Qc2 Qd7 16. Nbd2 Rfe8 17. Rad1 Rad8 18. c4 Bf5 19. Qb3 Be6 20. Kh1 Bf7 21. Qb2 Nd6 22. Rc1 Bh5 23. h3 h6 24. Qc2 Qf7 25. Kh2 g5 26. c5 Bg6 27. Qb2 Nf5 28. Nf1 Ne7 29. Bd2 Nd5 30. Ng3 Qd7 31. Ng1 h5 32. f3 h4 33. Ne4 Qf5 34. Ne2 Bh5 35. Rf1 Bf7 36. N2c3 Be6 37. Rce1 Qg6 38. Nd1 Bf5 39. Ne3 Bxe4 40. fxe4 Rxe4 41. Qb1 Kh7 42. Nf5 Ree8 43. Re4 Rxe4 44. Qxe4 Re8 45. Qg4 Rg8 46. Rf3 Rh8 47. Be1 Kg8 48. Nxh4 Qf7 49. Nf5 Qh5 50. Qe4 Kf8 51. Bd2 Qe8 52. Qd3 Qg6 53. Rf1 Rh7 54. g4 Bb8 55. Qe2 Qe8 56. Qf3 Qg6 57. h4 Ke8 58. h5 b6 59. Ng3 Kd7 60. Ne4 Rh6 61. Kg1 Qg8 62. cxb6 cxb6 63. axb6 Bf4 64. Nc5+ Kd8 65. b7 Kc7 66. Qa3 Bxd2 67. Nxa6+ Kd6 68. b8=Q+ Qxb8 69. Nxb8 Rh7 70. b5+ Ke6 71. Nxc6 Rd7 72. Qf8 Nf4 73. Rd1 Be3+ 74. Kf1 Nd5 75. Ra1 Nb6 76. Ke2 Bxd4 77. Rd1 Bc5 78. Qg8+ Rf7 79. Nd8+ Ke5 80. Kf3 Bd4 81. Qxf7 Kd6 82. Nb7+ Ke5 83. Qe8+ Kd5 84. Qc6+ Ke5 85. Qd6#
*[/pgn]

The 0.70 is on a scale where a clean pawn up is +1.00. However current Stockfish and Komodo Dragon versions (and I think some other top engines too) have switched to a scale where 1.00 is defined as the dividing line between a win and a draw, so obviously I would say 1.00 on that scale. These engines generally give about +1.4 or so to positions where White is up a healthy pawn for no compensation. Regarding the 3...Bc5 opening in the given game, it is certainly not "balanced" or even close to "normal" (meaning average White plus); the eval shown by SF15.1 after a 40 ply search on 20 threads was +0.44, way above par for White, but still not at all close to the 1.00 decisive line. I must admit to being surprised to see SF lose even from a +0.44 opening, that's still 0.56 away from losing. Perhaps the similarity of all the top NNUE engines, regardless of what net they use, makes draws very likely between them, but when one is Alpha-Beta like SF and the other MCTS like LCZero they are so different that the draw probability is not quite as overwhelming. That's a good sign for chess and at least means that chess960 isn't so hopelessly drawn for top engines as past results suggest, since at least a few of the positions are above the 0.50 plus mark, more than the 0.44 of this game.

[M ANSARI]

OMG !!! haven't looked at computer games for a while ... but really, that looked like aliens playing chess. Maybe the doubled pawns for black were just too much of a handicap and I wouldn't really consider this a balanced opening ... at least not for these incredibly strong engines. The play of the white side is just incredible ... the temporary pawn sac to exploit the advantage was so deep and really didn't look like a temporary pawn sac. It took 8 moves by white to regain the pawn in a knife edged middle game with heavy pieces hanging all over the board.

I am guessing we will see a lot of such games as engines become stronger and stronger. All us humans can do is just look at the games in awe.