It's never a good idea to overlook mate...

My opponent put up creative resistance in the following game, but eventually I found myself in a better position. It was unfortunate that I overlooked a very Jerome-ish possible move 20. However, it's never a good idea to overlook mate...

perrypawnpusher - Cibola
blitz, FICS, 2010

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5

An earlier contest between the two of us was a Semi-Italian Jerome Gambit: 3...h6 4.0-0 Bc5 5.Bxf7+ Kxf7 6.Nxe5+ Nxe5 7.Qh5+ Ng6 8.Qd5+ Ke8 9.Qxc5 Qe7 10.Qe3 Nf6 11.Nc3 c6 12.f4 b6 13.f5 Ne5 14.d4 Ba6 15.dxe5 Qxe5 16.Re1 Kf7 17.Qf3 Rhe8 18.Bf4 Qc5+ 19.Be3 Qb5 20.Bd4 Qxb2 21.e5 Nd5 22.e6+ Kg8 23.Qg4 Nxc3 24.Qxg7 checkmate, perrypawnpusher - Cibola, blitz, FICS, 2009.

My opponent also had scored in the past in one of his games with the Blackburn Shilling Jerome Gambit: 3...Nd4 4.Bxf7+ Ke7 5.Bxg8 Rxg8 6.d3 h6 7.Nxe5 d6 8.Ng6+ Kd7 9.0-0 b6 10.c3 Ne6 11.Nd2 Bb7 12.Nc4 Qg5 13.Nxf8+ Black resigned, Cibola - patitolo, blitz, FICS, 2005

4.Bxf7+

4...Kxf7 5.Nxe5+

My opponent had even played a straight Jerome Gambit, albeit a bit wobbly: 5.Ng5+ Qxg5 6.d3 Qxg2 White resigned, Cibola - Argo, blitz, FICS, 2003

5...Nxe5 6.Qh5+ Kf8

7.Qxe5 Be7

An interesting idea. Black has so many ways to go right in the Jerome Gambit.

8.d4 Bf6 9.Qf4 g5

This is overly energetic, however.

10.Qe3

Stronger was 10.Qf3. Even now I'm amused that when I consider that move in my mind, I think: but this leaves my d-pawn unprotected!

10... d6 11.O-O h6 12.f4

12...Kg7 13.e5 dxe5 14.fxe5 Be7 15.Qf3

The problem with this move is not 15...Qxd4+, which would cost Black a handful of tempos in return for a dubious pawn. It's that White's Queen needs more help, as in 15. Nc3 Be6 16. Ne4 followed by b3-b3 and Bc1-b2, with an even game.

15...Be6 16.Be3 Bd5 17.Qf2 20.Qe8 18.Nc3 c6

This move appears to cement Black's Bishop in the center, but has a weakness that my opponent and I overlooked.

19.Nxd5 cxd5

 Now 20.c4 should come to the mind of any Jerome Gambiteer, as 20...dxc4 21.d5 liberates the "Jerome pawns" and puts Black under pressure, e.g. 22...Qg6 22.Bxa7 when Black's pieces stumble over each other, while White plans Qf4-d4, supporting the pawns and preparing a discovered check.

20.c3 Qg6 21.Qf3

The game is about even. If White can snare a pawn or two more, he will have the advantage.

21...Rf8 22.Qxd5 Rxf1+ 23.Rxf1 h5

Black's 21st move was a mistake, and this move compounds it. Now there are pawns to feast upon.

24.Qxb7 h4 25.Qxa7

It is always nice to have five connected, passed pawns, but this is the first sign that I was not paying sufficient attention to what my opponent was planning.

25...h3 26.g3

Necessary was 26.Qb7 protecting g2. Black is now probably better.

26...Qe4 27.d5 Qg2 checkmate

It is unclear if White could have held the game after 27.Rf2 Qxe3, with five pawns vs two pieces, but it's never a good idea to overlook checkmate...