Engine-assisted game vs Stockfish, move 12 discussion

[MooMoo2]

The most popular move on the move 11 poll was ...f5. Stockfish played 12. c3, and the FEN is:
r1bqkb1r/5p1p/p1np4/1p1Npp2/4P3/N1P5/PP3PPP/R2QKB1R b KQkq - 0 12

Game so far: 1.e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nf6 5. Nc3 Nc6 6. Ndb5 d6 7. Bf4 e5 8. Bg5 a6 9. Na3 b5 10. Bxf6 gxf6 11. Nd5 f5 12. c3

Depth: 49 ply. Nodes searched: 1,218,382,516,080 (~1218 G)

[gd_barnes]

I think that 12...Bg7 is the only reasonable move.

[LaurV]

This move was a bit unexpected wasn't it?

Assuming we move nothing now, and white is to move, or we make a silly move like f4, his best attack is still Bxb5, axb5, Nxb5. Even with a bishop less, he put both knights in our house, and we have no place to escape with the king. This is without any engine support (but having in mind former discussions, based on engine support too), we can only avoid this attack with either defending that pawn more, or making place for the king to move to f8, to make the sacrifice futile. So, that is either Bg7, Be7, or Rb8. Also, Be6 seems interesting too, because after the sacrifice, we exchange the horse in d5 and he can not attack c7 with a single horse. But then after Be6, exf5 and we can't beat the pawn, because of the sacrifice on b5, so we must Bxd5 Qxd5, a bit empty there for us... not good.

So we need to pick from Bg7, Be7, or Rb8, and the first one looks indeed most promising, covering the king and defending f6 too (because after exf5, Bxf5, Qf3 we need to run with the bishop and he has Nf6+, mixing all our plans there).

Just for my curiosity, what is komodo's white reply to these 3 black moves? (to make sure I follow the right track)

[henryzz]

Not fond of 12...Be6 13.exf5 Bxf5 14.Qf3 Be6 15.Nf6+.
12...Rb8 13.exf5 Bxf5 14.Qf3 Be6 15.Nf6+ has similar problems with the knight.

12...Bg7 is my favourite currently. It avoids the weakness on f6.

[gd_barnes]

Originally Posted by LaurV

Just for my curiosity, what is komodo's white reply to these 3 black moves? (to make sure I follow the right track)

I am out of town for 10 days and don't have access to Komodo 10. You might try your engine or downloading the free Komodo 8.

I suggested Bg7 for us here because it is played in over 90% of games (239 out of 259) in the opening DB.

Looking at other suggested moves in the DB:
12...Be7 has only been played in one game out of 259. The game was a draw.
12...Rb8 has only been played in two games. White won both.

The second most played move in the DB is fxe4 with 9 out of 259. White scored 6-1-2 in these games as he played 13. Bxb5 in all of them and created a strong attack.

Therefore I strongly suggest Bg7 for us here. The most likely line is:
12...Bg7 13. exf5 Bxf5 14. Nc2. Here we can play O-O or Be6. I like our position with either and the DB shows less than a 3% win difference between white and black here. We are close to equalizing as we get to the point where there are few moves remaining in most opening DB's. There are few pieces swapped off so we will have some winning chances.

BTW, white's response on his move 12 is the 2nd most played response in the DB that I'm looking at and it has a much higher win % for white (39%-22% with 39% ties) than 12. Bd3 (37%-29% with 34% ties). So I feel that SF made the best move.

[WMHalsdorf]

12...Bg7 is the best move I see at the moment. It negates the white bishop sacrifice for what would be two pawns and a strong attack useless since we can now castle kingside.