Jerome Gambit: Stockfish 15.1 - Maximo

Here is the Stockfish 15.1 - Maximo game mentioned in the previous post.

Stockfish 15.1 - Maximo

Chess.com, 2023

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 

4...Kxf7 5.Nxe5+ Nxe5 6.d4

In its games in The Database, Stockfish prefers playing 6.Qh5+ to playing 6.d4 about 2 to 1.

Stockfish 15.1, analyzing independently (30 ply) sees 6.Qh5+ as about 1 pawn better than 6.d4. 

However, looking at chessplayers at large, things are a little bit different. 

Looking at all games in The Database, White prefers 6.Qh5+ over 6.d4 by over 3 to 1 (12,757 games to 3,716 games). White scores a bit better (57% vs 55%) with 6.Qh5+. 

Perhaps it comes down to whether the first player prefers to see his own Queen near the enemy King, or to see the enemy Queen near his own King.

6...Qh4 7.O-O Qxe4 8.dxc5 Nf6 

White is behind in material and development. Clearly, he has some work to do. He can hope to take advantage of Black's King's relative insecurity, and perhaps take advantage of Black's Queen's placement.

9.Bg5 Qf5 10.Bxf6 gxf6 

A forward-thinking recapture. Black opens the g-file with "thoughts" of putting a Rook on the file, to attack White's King.

If, instead, 10...Qxf6, keeping the pawn structure more intact, White would have 11.Nc3, planning Nd5, chasing Black's Queen back to d8 to prevent Nxc7.

11.Nc3 Rg8 12.Qd5+ Qe6 13.f4 Nc4 

Maximo may have evaluated 13...Qxd5 14.Nxd5 Ng6 15.Nxc7 differently than Stockfish 15.1, but that may well have been the better path to follow.

14.Qh5+ Kf8 

I looked at this move with the help of Stockfish 15.1. It preferred 14...Kg7 keeping the pesky enemy Queen from approaching. It evaluated the game after 14...Kf8 as "0.00" which is usually an indication that is sees a draw in its analysis. (I have mentioned before that when it comes to the Jerome Gambit, Stockfish analysis can show a "run for a draw prejudice" for White. It is good to see that it's play in this game is more dynamic.)

15.Qh6+ Rg7 16.Rae1 Ne3 

The Knight move looks awkward, but things are complicated enough that a Queen move would give White the advantage.

17.Rf2 

The drawing line mentioned above after move 14 is 17.f5 Qc6 18.Re2 Ng4 19.Re8+ Kxe8 20.Qxg7 Qxc5+ 21.Kh1 Nf2+ 22.Rxf2 Qxf2 23.Qg8+ Ke7 24.Qxh7+ Kf8 25.Qh6+ Kg8 26.Qg6+ Kh8 27.Qxf6+ Kg8 28.Qg6+ Kf8 29.Qh6+ Kg8 etc. 

With the text move White looks to double Rooks on the e-file while protecting his g-pawn.

17...b6 

Looking to put the Bishop on the a8-h1 diagonal and increase pressure on g2.

Keeping things level (or a slightly bit better for Black) was the Queen swap 17...Ng4 18.Rxe6 Nxh6 19.Rxf6+ Nf7 20.Nd5, although it would cost a pawn and be less active. 

18.f5 Nxf5 19.Qd2 

White's active piece play is beginning to turn the game to its advantage. The Knight at f5 will fall.

19...Qc4 20.Rxf5 Bb7 21.Re2 Kg8 22.b3 Qb4 23.Ne4 Qxd2 24.Nxf6+ 

24...Kf7 

It is interesting that Stockfish 15.1's analysis, after the game, prefers tucking the King away with 24...Kh8, while Maximo, in the game, prefers to make the King more active. Different evaluation functions. 

25.Rxd2 Kg6 26. Rf4 Rf8 27. Rdf2 bxc5 28. h4 d6 29. Rf5 Bc8 30. h5+ Kh6 31. Ng4+ Rxg4 32. Rxf8 Bb7 

I suspect that in a club player vs club player game, the advantage of the exchange might not be "winning", but top computer programs can squeeze out a win. 

In fact, Stockfish 15.1 rates White as being a Rook better at this point.

33.R8f7 Be4 34.Rxc7 Kxh5 35.Rxa7 Rg3 36.c4 Rd3 37.Kh2 Kg4 38.Raf7 Kg5 39.Rg7+ Bg6 40.Rc7 Kg4 41.Rc8 Kg5 42.Rf3 Rxf3 43.gxf3 Bf5 44.Rb8 Kf4 45.a4 Kxf3 

Black's active King can not balance White's active protected passed a-pawn.

A human chess master could now play 46.Rf8 Ke4 47.Rxf5 Kxf5 48.a5 and expect to hear "I resign".

Stockfish 15.1 marches on.

46.a5 Be4 47.a6 d5 48.cxd5 Bxd5 49.Rb5 Ke4 50.Rxc5 Bxb3 

White needs only one pawn to win - in 16 moves or less.

51.a7 Kd4 52.Rh5 Bf7 53.Rh4+ Kd3 54.a8=Q Bg6 55.Qd5+ Ke2 56.Kg3 Bc2 57.Rh2+ Ke3 58.Rd2 Bd3 59.Qxd3 checkmate