A french defence game

[Look]

Hi,

Kibitzing an on-line game :

[pgn]
1. e4 e6 2. d4 d5 3. Nc3 Bb4 4. e5 c5 5. a3 Bxc3+ 6. bxc3 Ne7 7. Nf3 { C19 French Defense: Winawer Variation, Positional Variation } O-O 8. Bd3 h6 9. g4 b6 10. g5 h5 11. h4 Nbc6 12. Be3 c4 13. Be2 Nf5 14. Nh2 g6 15. Bxh5 gxh5 16. Qxh5 Kg7 17. Ng4 Rh8 18. Nh6 Qg8 19. Rg1 Kf8 20. g6 Qg7 21. Kd2 Nxe3 22. gxf7 Rxh6 23. Qf3 Qxf7 24. Qxe3 Rxh4 25. Rg3 Ne7 26. Rag1 Nf5 27. Qg5 Bb7 28. Rf3 Rh5 29. Qg4 Ke7 30. a4 Rah8 31. a5 bxa5 32. Ra1 Rg8 33. Qf4 Ke8 34. Rxa5 Rh1 35. Rxa7 Rgg1 36. Re3 Rd1+ 37. Ke2 Nxd4+ 38. cxd4 Qxf4 { White resigns. } 0-1
[/pgn]

White played 9. g4 and an interesting game was played. In the next few moves both sides could have played better, producing nice variations.

[d] rnbq1rk1/pp2npp1/4p2p/2ppP3/3P2P1/P1PB1N2/2P2P1P/R1BQK2R b KQ - 0 9

[Lyudmil Tsvetkov]

the French Winaver is lost for black.

[d]r1bq1r2/p4pk1/1pn1p3/3pPnPQ/2pP3P/P1P1B3/2P2P1N/R3K2R w KQ - 0 1

white made a decisive mistake on move 17.
instead of Ng4, Qf3, followed by Ng4-f6 wins for white.

the place of that knight is on f6, where it is twice stronger than on h6.

[Lyudmil Tsvetkov]

see Komodo analysing a position like this one:

[d]r1b1q2r/5pk1/2n5/pp1pPpPP/2pP4/P1P1B3/2P1QP2/R3K2R w KQ - 0 6

which might arise from the main diagram, if white plays weak.

ply 1, white on move: +30cps
ply 2, black on move: -170cps
ply 3: +40cps
ply 4: -150cps
ply 5: +60cps
ply 6: -120cps
pl 7: +50cps
ply 8: -170cps

very funny indeed.

[Lyudmil Tsvetkov]

funny, SF does not spot Qf3 Rh8 h5 Ne3 fe3! Qg5 0-0-0 and white wins:

[d]r1b4r/p4pk1/1pn1p3/3pP1qP/2pP4/P1P1PQ2/2P4N/2KR3R b - - 0 4

other lines are more or less similar and lead to very convincing white scores.

[mbabigian]

Lost? From here? rnbqk1nr/pp3ppp/4p3/2ppP3/3P4/P1P5/2P2PPP/R1BQKBNR b KQkq - 0 6

Are there some correspondence games that decisively show all options fail? Seems unlikely.

Mike

[Lyudmil Tsvetkov]

Lost? From here? rnbqk1nr/pp3ppp/4p3/2ppP3/3P4/P1P5/2P2PPP/R1BQKBNR b KQkq - 0 6

Are there some correspondence games that decisively show all options fail? Seems unlikely.

Mike

let me see what this is:

[d]rnbqk1nr/pp3ppp/4p3/2ppP3/3P4/P1P5/2P2PPP/R1BQKBNR b KQkq - 0 6

[Lyudmil Tsvetkov]

Lost? From here? rnbqk1nr/pp3ppp/4p3/2ppP3/3P4/P1P5/2P2PPP/R1BQKBNR b KQkq - 0 6

Are there some correspondence games that decisively show all options fail? Seems unlikely.

Mike

let me see what this is:

[d]rnbqk1nr/pp3ppp/4p3/2ppP3/3P4/P1P5/2P2PPP/R1BQKBNR b KQkq - 0 6

seems very much like that to me.

exchanging bishops on a6 or castling long might still give black drawing chances, but otherwise the huge amount of available lines should be won for white, or at least very favourable.

sometimes, human and engines stats are counter-indicative.

still have not decided when exactly one should trust those, but one of the reasons for false positives might be an extremely difficult and deep position, like this one.

my engine stats from the main diagram(move 17 I posted) would hint at a dead draw or even slight black advanatge, but white is winning easily of course.

the position is simply too deep for engines and humans to play and evaluate correctly, but refined eval should show more than 80cps after bc3.

PS. yes, I know, human database on this opening gives white just a modest advantage, some moves like Qc7 lose badly, while Qa5 only slightly, but in the present case I am not certain how relevant such stats are.

[mbabigian]

I've always thought database statistics were useless. So we agree there. The tree is just too vast and the samples so tiny, that the win/loss ratio means zero in nearly all situations.

Certainly the original line given looks very bad for black. My IDeA analysis in this variation would need substantially more effort to show black is in big trouble after White's move 6, but I may divert it from other things later this week to further investigate this.

Black's main alternatives are currently 6 ...Qa5 and ...Ne7 as played in the game.

Currently the scores favor White responding Qg4 (0.24) over Nf3 (0.00) in the ... Ne7 continuation.

Looking at how easily black can get into trouble even when played by a computer, the variation looks dangerous. The engines routinely fail to see the pawn pushes on the king side and strategic retreats like your Qf3! That said, I'm always surprised how many resources for defense can be found when talking about variations so early in the game. I'd be surprised if black was lost after White's move 6, but considering the issues you mentioned with the sheer depth, it is possible.

Mike

[zullil]

funny, SF does not spot Qf3 Rh8 h5 Ne3 fe3! Qg5 0-0-0 and white wins:

[d]r1b4r/p4pk1/1pn1p3/3pP1qP/2pP4/P1P1PQ2/2P4N/2KR3R b - - 0 4

other lines are more or less similar and lead to very convincing white scores.

asmFish finds Qf3 quickly, so Stockfish should too.

Code: Select all

info depth 27 seldepth 40 multipv 1 time 9755 nps 10144614 score cp -51 lowerbound nodes 98960713 tbhits 0 hashfull 15 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 seldepth 40 multipv 1 time 10037 nps 10581027 score cp -43 lowerbound nodes 106201769 tbhits 0 hashfull 17 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 seldepth 40 multipv 1 time 10805 nps 11691859 score cp -33 lowerbound nodes 126330542 tbhits 0 hashfull 19 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 seldepth 40 multipv 1 time 12692 nps 13821887 score cp -17 lowerbound nodes 175427397 tbhits 0 hashfull 30 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 seldepth 40 multipv 1 time 15597 nps 16964628 score cp 3 lowerbound nodes 264597303 tbhits 0 hashfull 47 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 seldepth 40 multipv 1 time 22016 nps 22229699 score cp 31 lowerbound nodes 489409067 tbhits 0 hashfull 102 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 currmove h2g4 currmovenumber 2
info depth 27 currmove h5h7 currmovenumber 3
info depth 27 currmove e3f4 currmovenumber 4
info depth 27 currmove h5h6 currmovenumber 5
info depth 27 currmove e1d2 currmovenumber 6
info depth 27 currmove e1e2 currmovenumber 7
info depth 27 currmove e1c1 currmovenumber 8
info depth 27 currmove g5g6 currmovenumber 9
info depth 27 currmove h5g6 currmovenumber 10
info depth 27 currmove e3d2 currmovenumber 11
info depth 27 currmove e1d1 currmovenumber 12
info depth 27 currmove h1g1 currmovenumber 13
info depth 27 currmove h5h8 currmovenumber 14
info depth 27 currmove e3c1 currmovenumber 15
info depth 27 currmove f2f4 currmovenumber 16
info depth 27 currmove h2f3 currmovenumber 17
info depth 27 currmove h5g4 currmovenumber 18
info depth 27 currmove a1c1 currmovenumber 19
info depth 27 currmove a3a4 currmovenumber 20
info depth 27 currmove h2f1 currmovenumber 21
info depth 27 currmove h1f1 currmovenumber 22
info depth 27 currmove a1d1 currmovenumber 23
info depth 27 currmove a1a2 currmovenumber 24
info depth 27 currmove h5e2 currmovenumber 25
info depth 27 currmove e1g1 currmovenumber 26
info depth 27 currmove f2f3 currmovenumber 27
info depth 27 currmove e1f1 currmovenumber 28
info depth 27 currmove h5d1 currmovenumber 29
info depth 27 currmove a1b1 currmovenumber 30
info depth 27 currmove h5f7 currmovenumber 31
info depth 27 seldepth 41 multipv 1 time 24052 nps 23425287 score cp 26 nodes 563425009 tbhits 0 hashfull 114 pv h5f3 f8h8 h2g4 g7f8 g4f6 c6e7 h4h5 e7g8 e1c1 g8f6 e5f6 f8e8 e3f4 e8d7 f4e5 d7c6 g5g6 f5h6 a3a4 a7a5 f3f4 c6b7 c1d2 c8d7 g6g7 h8h7 d1a1 h6f5 f4g4 d7c6 a1a2 b7a7 h1b1 f5h6 g4f4 h6g8 f4g5 h7h6

and after more time

Code: Select all

info depth 42 seldepth 76 multipv 1 time 854389 nps 36479390 score cp 120 nodes 31167589739 tbhits 0 hashfull 999 pv h5f3 f8h8 h2g4 f5h4 f3f6 d8f6 g5f6 g7f8 e3h6 f8e8 h1h4 e8d7 e1e2 d7c7 a1h1 c8d7 g4e3 a7a5 h6f4 h8h4 h1h4 a8g8 h4h7 c6d8 f4h6 c7c6 h6g7 c6b5 h7h1 g8e8 f2f4 b5c6 e2f3 c6b5 e3g4 b5c6 h1a1 c6c7 a1g1 c7c6 g4e3 c6b5 g1a1 b5c6 a1b1 e8g8 f3e2 g8e8 b1h1 c6c7 h1h7 c7c6 e2d2

[Lyudmil Tsvetkov]

funny, SF does not spot Qf3 Rh8 h5 Ne3 fe3! Qg5 0-0-0 and white wins:

[d]r1b4r/p4pk1/1pn1p3/3pP1qP/2pP4/P1P1PQ2/2P4N/2KR3R b - - 0 4

other lines are more or less similar and lead to very convincing white scores.

asmFish finds Qf3 quickly, so Stockfish should too.

Code: Select all

info depth 27 seldepth 40 multipv 1 time 9755 nps 10144614 score cp -51 lowerbound nodes 98960713 tbhits 0 hashfull 15 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 seldepth 40 multipv 1 time 10037 nps 10581027 score cp -43 lowerbound nodes 106201769 tbhits 0 hashfull 17 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 seldepth 40 multipv 1 time 10805 nps 11691859 score cp -33 lowerbound nodes 126330542 tbhits 0 hashfull 19 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 seldepth 40 multipv 1 time 12692 nps 13821887 score cp -17 lowerbound nodes 175427397 tbhits 0 hashfull 30 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 seldepth 40 multipv 1 time 15597 nps 16964628 score cp 3 lowerbound nodes 264597303 tbhits 0 hashfull 47 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 seldepth 40 multipv 1 time 22016 nps 22229699 score cp 31 lowerbound nodes 489409067 tbhits 0 hashfull 102 pv h5f3
info depth 27 currmove h5f3 currmovenumber 1
info depth 27 currmove h2g4 currmovenumber 2
info depth 27 currmove h5h7 currmovenumber 3
info depth 27 currmove e3f4 currmovenumber 4
info depth 27 currmove h5h6 currmovenumber 5
info depth 27 currmove e1d2 currmovenumber 6
info depth 27 currmove e1e2 currmovenumber 7
info depth 27 currmove e1c1 currmovenumber 8
info depth 27 currmove g5g6 currmovenumber 9
info depth 27 currmove h5g6 currmovenumber 10
info depth 27 currmove e3d2 currmovenumber 11
info depth 27 currmove e1d1 currmovenumber 12
info depth 27 currmove h1g1 currmovenumber 13
info depth 27 currmove h5h8 currmovenumber 14
info depth 27 currmove e3c1 currmovenumber 15
info depth 27 currmove f2f4 currmovenumber 16
info depth 27 currmove h2f3 currmovenumber 17
info depth 27 currmove h5g4 currmovenumber 18
info depth 27 currmove a1c1 currmovenumber 19
info depth 27 currmove a3a4 currmovenumber 20
info depth 27 currmove h2f1 currmovenumber 21
info depth 27 currmove h1f1 currmovenumber 22
info depth 27 currmove a1d1 currmovenumber 23
info depth 27 currmove a1a2 currmovenumber 24
info depth 27 currmove h5e2 currmovenumber 25
info depth 27 currmove e1g1 currmovenumber 26
info depth 27 currmove f2f3 currmovenumber 27
info depth 27 currmove e1f1 currmovenumber 28
info depth 27 currmove h5d1 currmovenumber 29
info depth 27 currmove a1b1 currmovenumber 30
info depth 27 currmove h5f7 currmovenumber 31
info depth 27 seldepth 41 multipv 1 time 24052 nps 23425287 score cp 26 nodes 563425009 tbhits 0 hashfull 114 pv h5f3 f8h8 h2g4 g7f8 g4f6 c6e7 h4h5 e7g8 e1c1 g8f6 e5f6 f8e8 e3f4 e8d7 f4e5 d7c6 g5g6 f5h6 a3a4 a7a5 f3f4 c6b7 c1d2 c8d7 g6g7 h8h7 d1a1 h6f5 f4g4 d7c6 a1a2 b7a7 h1b1 f5h6 g4f4 h6g8 f4g5 h7h6

and after more time

Code: Select all

info depth 42 seldepth 76 multipv 1 time 854389 nps 36479390 score cp 120 nodes 31167589739 tbhits 0 hashfull 999 pv h5f3 f8h8 h2g4 f5h4 f3f6 d8f6 g5f6 g7f8 e3h6 f8e8 h1h4 e8d7 e1e2 d7c7 a1h1 c8d7 g4e3 a7a5 h6f4 h8h4 h1h4 a8g8 h4h7 c6d8 f4h6 c7c6 h6g7 c6b5 h7h1 g8e8 f2f4 b5c6 e2f3 c6b5 e3g4 b5c6 h1a1 c6c7 a1g1 c7c6 g4e3 c6b5 g1a1 b5c6 a1b1 e8g8 f3e2 g8e8 b1h1 c6c7 h1h7 c7c6 e2d2

from that position you should squeeze at least +450cps.

so, your SF has nothing to be proud of, raving again somewhere in the fringe lines...