Move 23b discussion: Everyone vs stockfish

[MooMoo2]

The poll for move 22 just closed, and the most popular move was Qxf6. Stockfish responded with 22...R1e2+, and the FEN is:
4r1k1/pp3p1p/5Q2/3p4/2n5/1N3P2/PPP1rKPP/8 w - - 1 23

Game so far: 1.e4 e6 2. d4 d5 3. Nd2 c5 4. Ngf3 Nf6 5. exd5 exd5 6. Bb5+ Bd7 7. Bxd7+ Nbxd7 8. O-O Be7 9. dxc5 Nxc5 10. Nb3 Nce4 11. Nfd4 O-O 12. Nf5 Re8 13. Nxe7+ Rxe7 14. f3 Nd6 15. Bg5 Nc4 16. Bxf6 gxf6 17. Qd4 Qb6 18. Rab1 Qe6 19. Rfe1 Qxe1 20. Rxe1 Rxe1+ 21. Kf2 Rae8 22. Qxf6 R1e2+

[LaurV]

I think we are very good here with Kg3.

I know Gary advocated Kg1 (and Kf1 is bad, due to Ne3, we can't take the rook because we lose the queen, so we lose g2 and are forced in the corner, this is bad for us), but I am thinking that Kg3 avoids the future checks on e1, and also weakens the R2e6 move, because after Ke3, R2e6, Qf4, Rg6+, Kh3, black has no move anymore, any of his moves creates sente for us, his rook can't live line 8, etc. This shorts the game, comparing with Kf1. If after Kh3, Re5 (threatening mate in h5) or if Ne3 (targeting g2) then white g3 or g4, and it will be very difficult for black to get those rooks out of there, in which time our queen can easily clear the flank, making our pawns free. That is bad for black. If Rb6, then Nc5 works in our advantage bringing the horse close to the black king (targeting mate with horse+queen there, the queen alone can not mate).

So, say 23. Kg3, what next? If ...Ne3 (the most probable choice from SF, due to attack variation on g2), then we have eternal check, his king can not get out of f8-g8-h8, because if it gets out, it blocks the rook, here we may win the game.

Like in this short version (without including repetitions): 23. Kg3 Ne3 24. Qg5+ Kf8 25. Qh6+ Ke7 26 Kh3 and now he can't beat the pawn in g2 because it loses the horse. So, right now, he can't move the lower rock, because he loses the horse (or the rook, if he put it in e1 to keep control the horse, then Qh4+ and the rook is lost), he can't move the king (because white Nc5, possible mate in b8-d8, if for example Kd7, Nc5, etc), he can not move the higher rook (and lose the defense, in fact, having the rooks not on the same line or column is strategically bad for black here), so he can only move pawns, or the horse. So, 26... Nxc2, then - here is the trick - 27. Qh4+(!). Now he either goes back to f8, and we repeat all, or he advances to the middle of the table, where it is at our mercy, we even may win here if he plays so, our queen is extremely mobile there, especially supported by the horse and by the pawn in column f.

[gd_barnes]

Excellent analysis LaurV! I now agree that 23. Kg3 is better than Kg1. I had dismissed it because it looked scary putting our king in front of our pawns. As you demonstrated, a SF response of 23...Ne3 is technically a mistake if he is playing for a win as it allows the quick perpetual check or eventual gain of material by us. Also the attempt with 23...R2e6 followed by Rg6+ and/or Ne3 and/or Re5 is easily covered up by us and we have open lines for our Queen, knight, and pawns.

Your analysis begs the question: Would SF have been better to immediately play 22...R2e6?

[WMHalsdorf]

23. Kg3 avoids all kinds of threats involving SF's knight in combination the rooks and oddly the pawns protect out king.

[richs]

I agree with LaurV's analysis also.

[MooMoo2]

Originally Posted by gd_barnes

Excellent analysis LaurV! I now agree that 23. Kg3 is better than Kg1. I had dismissed it because it looked scary putting our king in front of our pawns. As you demonstrated, a SF response of 23...Ne3 is technically a mistake if he is playing for a win as it allows the quick perpetual check or eventual gain of material by us. Also the attempt with 23...R2e6 followed by Rg6+ and/or Ne3 and/or Re5 is easily covered up by us and we have open lines for our Queen, knight, and pawns.

Your analysis begs the question: Would SF have been better to immediately play 22...R2e6?

According to Stockfish's analysis, playing 22...R1e6 would have resulted in a +0.46 pawn advantage for white. Stockfish may want to avoid draws, but not at the cost of worsening its position by half a pawn (the exact threshold may even be a quarter pawn or less).

After move 22, the cost to avoid a draw only gets larger. If Stockfish responds with 23...R2e6 instead of Ne3, it results in a +0.75 pawn advantage for white.