Monday, December 4, 2017

Jerome Gambit: Never Knew What Hit Him, Either

I have been sharing some recently uncovered games by Ukranian player Vladymyr Yurev, online at InstantChess.com. It is clear that he and his opponents are playing for fun, as evidenced by the nasty, brutish and short wins by White.

Here is a game where Vladymyr took it seriously on the chin. I suspect he chuckled and set the pieces up again.

Vladymyr  Yurev - GN ITA
15 0, InstantChess, 2017

1.e4 e5 2.Nf3 Nc6 3.Bc4 h6 


The Semi-Italian opening, generally played as a safety first line. Not so, if White wants to get all Jerome-ish.

4.Bxf7+ Kxf7 5.d4 exd4 6.Nxd4 Qf6 7.Nf5 d6


Uh, oh.. Things don't seem to be going smoothly for White.

8.Qd5+ Be6 9.Nxd6+ 

The start of an irrational streak, the kind of thing that you see when your opponent's clock is almost expired, and you are willing to try anything to get him to use up those last precious seconds thinking...

9...Bxd6 10.Qxe6+ Qxe6 11.e5 


Okay, so White is going to blow everything up and start all over, next game.

11...Qxe5+ 12.Kd2 Qd4+ 13.Ke2 Re8+ 14.Kf3 Ne5+ 

Or 14...Qe4#.

15.Kg3 Nd3+ 

Or 15...Qg4#.

16.Kh3 Nxf2 checkmate


Oh, well, as the song goes, "Two out of three ain't bad."

Saturday, December 2, 2017

Jerome Gambit: Never Knew What Hit Them (Part 2)

As mentioned in the previous post, recently I was exploring the internet and ran across a number of fun games by Vladymyr Yurev, of Ukraine, at InstantChess.com. Some were Jerome Gambits, some were Jerome-ish.

Clearly some of his opponents did not know what to make of his openings, and succumbed quickly.

Here is another example.

Vladymyr  Yurev - Elsid
15 0, Instant Chess, 2017

1.e4 e5 2.Nf3 Nc6 3.Bc4 h6 


The Semi-Italian Opening. Safety first.

4.Bxf7+ Kxf7 5.d4 Nf6 6.dxe5 Nxe4 7.Qd5+ Ke8 Black resigned


Black will drop his Knight on e4, remaining a pawn down, but it is clear that his resignation had to do with not knowing what hit him.

Thursday, November 30, 2017

Jerome Gambit: Never Knew What Hit Them (Part 1)

I was exploring the internet the other day, and ran across a number of fun games by Vladymyr Yurev, of Ukraine, at InstantChess.com. Some games were Jerome Gambits, some were Jerome-ish.

Clearly some of his opponents did not know what to make of his openings, and succumbed quickly.

Here is one example.

Vladymyr  Yurev - MELVYN20
Instant Chess, 2017

1.e4 e5 2.Nf3 Nc6 3.Bc4 h6 



The Semi-Italian Opening. Black pursues safety by keeping the enemy Knight off of g5.

4.Bxf7+ 

Not everyone waits for ...Bc5 before sacrificing.

4...Kxf7 5.d4 Ke8 6.d5 Nb8 7.Nxe5 d6 8.Qh5+ Ke7 9.Qf7 checkmate

Ouch!

Nice work, Mr. Yurev!


Tuesday, November 28, 2017

Jerome Gambit: Been Around A While

It can be fun to play over the games of experienced Jerome Gambit players and watch their struggles, successes and failures. The games of Petasluk show up in The Database starting in 2004 - he has been around the Jerome universe for quite some time.

The following game shows how a deadly center break-through and attack on the King can proceed when Black discontinues his defenses prematurely.

Petasluk - valli
5 0 blitz, FICS, 2017

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 




4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Kf8 



A solid defense that avoids the risks of 6...Kf6. If Black wishes to develop his Rook at h8, however, the King will need to move again.

7.Qxe5 d6 8.Qg3 Nf6 9.d3 Kf7 



There are 19 games in The Database with this position. White scores 53%. White's Queen puts pressure on the Kingside, even as Black prepares to castle-by-hand (something he never accomplishes).

Petasluk has had significant experience with other defensive tries by Black:

9...h6 10.O-O Be6 (10...Kf7 11.Nc3 Rf8 12.Be3 Bb6 13.d4 Kg8 14.f4 Qe8 15.e5 dxe5 16.fxe5 Nd7 17.Bxh6 Rxf1+ 18.Rxf1 Qe7 19.Bg5 Bxd4+ 20.Kh1 Qxe5 21.Bf4 Qf6 22.Nd5 Qa6 23.Re1 Qxa2 24.Re8+ Kf7 25.Re7+ Kg8 26.Nxc7 Rb8 27.Ne6 Qb1+ White resigned,  Petasluk - leninas, FICS, 2013) 11.Nc3 c6 12.Bd2 b5 13.a3 a5 14.Ne2 Qb6 15.c3 d5 16.e5 Ng4 17.d4 Be7 18.h3 Nxe5 19.Qxe5 Bf7 20.Ng3 Bf6 21.Qf5 Re8 22.Rae1 c5 23.Rxe8+ Kxe8 24.Qc8+ Bd8 25.Re1+ Kf8 26.Nf5 cxd4 27.Nxd4 g6 28.Nc6 Kg7 29.Nxd8 Rxd8 30.Qg4 h5 31.Qg3 Rf8 32.Be3 Qf6 33.Bd4 Qxd4 34.cxd4 b4 35.Re7 bxa3 36.bxa3 Kh6 37.Qf4+ Kg7 38.Qe5+ Kg8 39.g4 hxg4 40.hxg4 a4 41.f4 Kh7 42.f5 Kh6 43.fxg6 Bxg6 44.Qe3+ Rf4 45.Qxf4 checkmate, Petasluk - caryoscelus, FICS, 2016

9...Be6 10.Bg5 Bf7 11.c3 h6 12.Bxf6 Qxf6 13.O-O Kg8 14.d4 Bb6 15.f4 Kh7 16.Nd2 Rhf8 17.e5 dxe5 18.fxe5 Qg6 19.Nf3 Bd5 20.Nh4 Qxg3 21.hxg3 Rae8 22.Kh2 c6 23.Nf5 Be6 24.Nd6 Rxf1 25.Rxf1 Re7 26.Rf4 Bxa2 27.g4 Bb1 28.c4 Ba5 29.Rf1 Bg6 30.Rf2 Be1 31.Re2 Bh4 32.g3 Bg5 33.Rf2 a6 34.Rf3 b5 35.cxb5 axb5 36.b4 h5 37.gxh5 Bxh5 White forfeited on time, Petasluk - wsilaenchess, FICS, 2014;

9...Qd7 10.h3 Kf7 11.Nc3 c6 12.Bd2 Rf8 13.O-O Kg8 14.Kh1 Qe7 15.f4 Nh5 16.Qf3 Qf7 17.Ne2 Qg6 18.f5 Qf7 19.g4 Nf6 20.c3 h6 21.Nf4 Re8 22.b3 d5 23.Rae1 dxe4 24.dxe4 Bd7 25.e5 Nd5 26.e6 Qe7 27.exd7 Qxd7 28.Ne6 Bb6 29.c4 Nf6 30.Bc3 Qf7 31.h4 Re7 32.g5 hxg5 33.Nxg5 Qf8 34.Ne6 Qf7 35.Re2 Rae8 36.Rfe1 Qh5 37.Qxh5 Nxh5 38.Bd2 Ng3+ 39.Kg2 Nxf5 40.Nf4 Nxh4+ 41.Kg3 Nf5+ 42.Kg4 Nh6+ 43.Kg5 Rxe2 44.Rxe2 Rxe2 45.Nxe2 Bd8+ 46.Kh5 Nf7 47.Kg4 Kh7 48.Nf4 Nh6+ 49.Kf3 g5 50.Ne6 Be7 51.Bxg5 Nf7 52.Bxe7 Ne5+ 53.Ke4 Ng6 54.Ba3 Kh6 55.Nd8 Kh5 56.Nxb7 Kg4 57.Nd8 Black forfeited on time Petasluk - Vukasin, FICS, 2014;

9...Ng4 10.O-O Bd4 (10...h5 11.h3 h4 12.Qf4+ Nf6 13.Nc3 c6 14.Be3 Bxe3 15.fxe3 Qe7 16.d4 Kg8 17.e5 dxe5 18.dxe5 Nd5 19.Nxd5 cxd5 20.Rad1 Be6 21.Rd2 Rf8 22.Qa4 Rxf1+ 23.Kxf1 Qg5 24.Qe8+ Kh7 25.Qxe6 Qxe3 26.Qxd5 Rf8+ White resigned, Petasluk - UNPREDICTABLE, FICS, 2011) 11.h3 Be5 12.Qf3+ Nf6 13.c3 d5 14.Bg5 h5 15.Nd2 Bg4 16.Qe3 dxe4 17.d4 Bd6 18.Nxe4 Bf5 19.f3 h4 20.Rae1 Bg3 21.Re2 Qd7 22.Nc5 Qf7 23.Bxf6 gxf6 24.b3 Bd6 25.Nxb7 Kg7 26.Nxd6 cxd6 27.Qd2 Rag8 28.Rfe1 Kh7 29.Re7 Qxe7 30.Rxe7+ Rg7 31.Rxg7+ Kxg7 32.Qf4 Black forfeited on time, Petasluk - UltraMN, FICS, 2014;

9...c6 10.O-O Qb6 11.Nc3 Kf7 12.Na4 Qa5 13.Nxc5 Qxc5 14.c3 h6 15.Be3 Qe5 16.f4 Qh5 17.Rae1 Rf8 18.e5 Nd5 19.Bd2 Qg4 20.Qf2 Bf5 21.h3 Qg6 22.g4 Bxd3 23.f5 Qh7 24.e6+ Ke7 25.Qh4+ Nf6 26.Rf3 Be4 27.Rfe3 d5 28.c4 Rh8 29.Bb4+ Ke8 30.cxd5 cxd5 31.Rc1 h5 32.g5 Qxf5 33.gxf6 gxf6 34.Rf1 Rg8+ 35.Kh2 Qxf1 36.Rg3 Qh1 checkmate, Petasluk - Reisswolf, FICS, 2011;

9...Qe7 10.O-O Kf7
(10...Bd7 11.Nc3 Re8 12.Bg5 h6 13.Nd5 Qe6 14.Bxf6 gxf6 15.Nxc7 Qg8 16.Nxe8 Qxg3 17.hxg3 Kxe8 18.Kh2 h5 19.f4 h4 20.gxh4 Rxh4+ 21.Kg3 Rg4+ 22.Kf3 f5 23.Rae1 Bc6 24.c3 fxe4+ 25.dxe4 Bb5 26.Kxg4 Black resigned Petasluk - Schallopp, FICS, 2008) 11.Nc3 c6 12.Bg5 Rf8 13.Bxf6 Qxf6 14.Kh1 Kg8 15.f4 Qg6 16.Qh4 Qg4 17.Qxg4 Bxg4 18.h3 Bd7 19.g4 h6 20.f5 Rae8 21.Rae1 Kf7 22.Ne2 Rh8 23.c3 d5 24.d4 Bb6 25.e5 g6 26.e6+ Bxe6 27.fxe6+ Kxe6 28.Nf4+ Kd6 29.Nxg6 Rxe1 30.Rxe1 Rg8 31.Nf4 Rf8 32.Ng6 Rf3 33.Kg2 Rd3 34.Nf4 Rd2+ 35.Re2 Rxe2+ 36.Nxe2 c5 37.Kf3 Ke6 38.h4 Kf6 39.dxc5 Bxc5 40.Nd4 Bxd4 41.cxd4 b6 42.b4 a5 43.bxa5 bxa5 44.a4 Kg6 45.Kf4 Kf6 46.g5+ hxg5+ 47.hxg5+ Kg6 48.Kg4 Kg7 49.Kf5 Kf7 50.g6+ Kg7 51.Kg5 Black resigned, Petasluk - pavlo, FICS, 2009;

9...h5 10.Bg5 h4 11.Qf4 Qe7 12.Nc3 Bd4 13.Nd5 Qf7 14.c3 Be5 15.Qd2 Nxd5 16.exd5 Bf5 17.d4 Bf6 18.Bxf6 Qxf6 19.O-O Re8 20.Rfe1 Kf7 21.Re3 Rxe3 22.fxe3 Qg5 23.Rf1 Kg6 24.Qf2 Re8 25.Qxf5+ Qxf5 26.Rxf5 Kxf5 27.Kf2 g5 28.h3 Ke4 29.Ke2 Rf8 30.c4 c6 31.dxc6 bxc6 32.b4 a6 33.a4 Rb8 34.b5 cxb5 35.axb5 axb5 36.cxb5 Rxb5 37.Kf2 Rb3 38.g3 hxg3+ 39.Kxg3 Rxe3+ 40.Kg4 Kxd4 41.Kxg5 Rxh3 42.Kf5 Re3 43.Kf4 Re8 44.Kf5 Kc4 45.Kf4 d5 White resigned, Petasluk - fluigi, FICS, 2009;

9...Nh5 10.Qf3+ Nf6 11.O-O h6 12.Qe2 Bg4 13.Qd2 Ke7 14.h3 Be6 15.Nc3 Qd7 16.Kh2 Raf8 17.f4 Kd8 18.f5 Bf7 19.a3 Kc8 20.b4 Bd4 21.Bb2 Be5+ 22.Kh1 Nh5 23.Rf3 g5 24.Rb1 g4 25.hxg4 Ng3+ 26.Kg1 h5 27.g5 Bd4+ 28.Kh2 h4 29.Nd5 Bxd5 30.Bxd4 Nxf5 31.Bxh8 Ne3 32.Rxf8+ Black resigned, Petasluk - brittaundvolker, FICS, 2009;

9...g6 10.O-O Kg7 11.Qf4 Nh5 12.Qh6+ Kf7 13.Nd2 Qf8 14.Qxf8+ Rxf8 15.Nf3 Kg7 16.d4 Bb6 17.c3 Bg4 18.Nd2 Rae8 19.f3 Bd7 20.Nc4 Rf7 21.Bd2 Bb5 22.b3 Bxc4 23.bxc4 c6 24.a4 a6 25.Rab1 Ba7 26.g3 Ref8 27.Kg2 Nf6 28.Rbe1 Nd7 29.h4 Re8 30.Bf4 d5 31.cxd5 cxd5 32.e5 Re6 33.Bd2 Rfe7 34.f4 Rc6 35.g4 Rc4 36.a5 Bb8 37.f5 gxf5 38.gxf5 Kf8 39.Bh6+ Ke8 40.f6 Rf7 41.Bg7 Nf8 42.Bxf8 Kxf8 43.e6 Rfc7 44.e7+ Kf7 45.e8=Q checkmate, Petasluk - Chaarl, FICS, 2009;

and 9...Qe8 10.O-O Qg6 11.Qf4 Bh3 (11...Qg4 12.Qd2 Ke7 13.Nc3 Be6 14.d4 Bb4 15.e5 Ne4 16.Nd5+ Bxd5 17.Qxb4 a5 18.exd6+ cxd6 19.Qe1 Kd7 20.f3 Qg6 21.fxe4 Bxe4 22.Qg3 Qxg3 23.hxg3 Rhf8 24.Bf4 h6 25.c4 g5 26.Be3 Bd3 27.Rxf8 Rxf8 28.c5 d5 29.b3 Kc6 30.Rd1 Be4 31.a3 Bc2 32.Rd2 Bxb3 33.Rb2 a4 34.Rf2 Rxf2 35.Kxf2 Bd1 36.Ke1 Bg4 37.Kd2 Kb5 38.Kc3 Bd1 39.Bf2 Be2 40.Be3 Bf1 41.Kd2 Bxg2 42.Ke2 Be4 43.Kd2 Kc4 44.Bf2 Kb3 45.Be1 Kxa3 46.Kc3 Ka2 47.Kb4 Bc2 48.Bc3 Bd3 49.Ka5 a3 50.Kb6 Kb3 51.Kxb7 Kxc3 White forfeited on time, Petasluk - juany, FICS, 2007) 12.Qf3 Bg4 13.Qf4 Re8 14.Nc3 Re7 15.Kh1 Rf7 16.f3 Bd7 17.Bd2 Nh5 18.Qh4 Nf6 19.f4 Qg4 20.Qe1 Nh5 21.f5 Ke8 22.Nd5 Kd8 23.Ne3 Bxe3 24.Qxe3 Rhf8 25.Rf2 a6 26.Raf1 g6 27.fxg6 Qxg6 28.Rxf7 Rxf7 29.Rg1 Rg7 30.g3 Nf6 31.Qa7 Ng4 32.Qxb7 Bc8 33.Qd5 Qf6 34.Kg2 Ne5 35.Rf1 Qg6 36.Qb3 drawn, Petasluk - godelllll, FICS, 2009

10.Nc3 


Or 10.O-O, which transposes, 10...Rf8 11.Nc3 Kg8 (11...a6 12.Bg5 Kg8 13.Kh1 Qe8 14.f4 Nh5 15.Qf3 h6 16.g4 hxg5 17.gxh5 Rxf4 18.Qg2 Qxh5 19.Nd5 Bh3 20.Nxf4 gxf4 21.Qf2 Bxf1 22.Qxf1 Be3 23.d4 Rf8 24.Re1 Rf6 25.Re2 Rg6 26.Rg2 Rxg2 27.Qxg2 Qd1+ White resigned, Petasluk - mattzig, FICS, 201412.Bd2 Kh8 13.Kh1 Nh5 14.Qg5 Qxg5 15.Bxg5 Rxf2 16.Nd5 Rxf1+ 17.Rxf1 Bd7 18.Nxc7 Bc6 19.Nxa8 Black resigned, Petasluk - jinhuan, FICS, 2016

10...c6 11.O-O Bb6 

12.Bg5 Bc7 13.f4 h6 14.Bh4 Qd7 15.h3 b5 



Black has reinforced his center and decides to expand on the Queenside, perhaps as a diversion. He is overlooking White's growing menace.

16.Rae1 a6 

This encourages White to break in the center.

17.e5 dxe5 18.fxe5 Qd4+ 19.Kh1 Be6 


Black will have to give back his extra piece, and his King is in trouble.

20.Re4 Qd7 21.Bxf6 Kg8 22.Ne2 Rf8


Black is defending, but is handicapped by his undeveloped Rook at h8.

23.d4 Bd8 24.Ref4 Rf7 

He could have tried 24...Rh7, but 25.Bxg7 would have led to a series of exchanges that would have left White simply a handful of pawns ahead, e.g. 25...Rxf4 26.Bxh6+ Qg7 27.Qxg7+ Rxg7 28.Nxf4.

25.Bxd8 Rxf4 26.Nxf4 Qxd8 27.Nxe6 


The smoke has cleared. Whie is a piece and a couple of pawns ahead, with a deadly attack.

27...Qe7 28.Rf8+ Kh7 29.Qd3+ g6 30.Rxh8+ Kxh8 31.Qxg6 a5 32.Qxh6+ Kg8 33.Qg6+ Kh8 Black resigned


Sunday, November 26, 2017

Jerome Gambit: Reverse Psychology

I always enjoy the advance of the "Jerome pawns" in different attacking Jerome Gambit games.

There is a sub-group of games, however, where White's psychological ploy is to use his extra pawns to build a fortress, and then challenge Black - with more material, hence, the advantage - to do his worst.

The following game is an extreme version of the latter idea. 

Petasluk - Caarreeyy
5 0 blitz, FICS, 2017

1 e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 



4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Ng6 7.Qxc5 d6 8.Qe3 Nf6 



9.d3 Re8 10.f3

Petasluk has arrived at this position 17 times before.

Black has got to be thinking: How hard can this be?

10...Kg8 11.O-O Kh8

The Database sees this "Hmmm, let me think about it" move as a novelty.

12.b3 Nd5 13.Qf2 Qf6 14.c3 Ndf4 15.Qc2 b6 16.Bb2 



Right now Black seems closer to mounting an attack.

16...Ba6 17.c4 Qg5 

Aggressive looking, but Stockfish 8, instead, suggests winning a couple of pawns with the flurry 17...Ne5 18.Nc3 Nexd3 19.g3 Nxb2 20.gxf4 Nxc4 21.bxc4 Bxc4 22.Ne2 Bxe2 23.Qxe2 Qxf4 when Black's advantage is clear, if not exciting.

18.Nc3 Nh4 

Things are beginning to look scary for White, but his pawns help out.

19.g3 Nh3+ 20. Kh1 Ng6 21. Rae1 Rf8 



Sometimes I recommend the Jerome Gambit as a way to help the second player work on defensive skills. Here, you see White working as well.

22.Qg2 Qh5 23.Nd5 Rac8 24.Ne3 Bb7 



This is a strange kind of position to arise out of a gambit. Even stranger, Stockfish 8 gives White a slight edge.

Black decides he can invest an exchange and a pawn in his attack.

25.Nf5 Rxf5 26.exf5 Ne5 27.Bxe5 dxe5 28.Rxe5 Ng5 



Black's pressure along the a8-h1 diagonal, especially with the targets - the pawn at f3, the Queen at g2, the King at h1 - seem to give him hope. Yet, the fact that White has a Rook and 3 pawns for a couple of pieces also reassures the first player.

29.f6

A loss of patience. White would do better to consolidate with 29.g4 Qh4 30.d4 followed by d5, stifling the enemy Bishop's pressure. 

29... gxf6 30.g4 Qg6 31.Re3 Re8 32.Rxe8+ Qxe8 



33.Qg3

Understandably wanting to get the Queen off of the deadly diagonal, but it was time to return to defense - and allow a draw by repetition, i.e. 33.d4 Nxf3 34.d5 Ne1 35.Qg3 Qe4+ 36.Kg1 Qd4+ 37.Kh1 Qe4+ etc. 

33...Qe3

There was also nothing wrong with 33...Nxf3 34.Rxf3 Qe2.

White is in serious trouble.

34.h4 Nxf3 35.Qxc7 

The game has reached a very curious, and critical point.

Black seems to have a win - but only one move will bring it about.

It will not simply be enough to exchange Queens, as after 35...Qe5 36.Qxe5 fxe5 37.Rf7 White can probably hold the R vs 2 pieces draw. 

He can, for example, win the exchange with the cute 35...Nh2+ 36.Qxb7 Nxf1, but after 37.Qf7 his exposed King will lead to a draw.

No, Black needs to win the exchange the other way: 35...Nd2+! 36.Qxb7 Qh3+! 37.Kg1 Qxf1+ when he can pose greater threats to White's King after 38.Kh2 Nf3+ 39.Kg3 Qg1+ 40.Kf4 Nxh4 41.Qa8+ Kg7 42.Qxa7+ Kh6


Black's King is safer




analysis diagram





35...Qxd3 

Black still looks like he has great pressure - but, actually, two pieces are hanging. The cool and rational Stockfish 8 adds that  White now has a checkmate in 28.

Chess!

36.Qb8+ Kg7 37.Qxb7+ Kh6 38.Qxf3 Black resigned



Well, that changed quickly...

Friday, November 24, 2017

Jerome Gambit Declined: Long But Not Winding Road

The following is one of two recent Jerome Gambit Declined games played between Petasluk (408 games in The Database, scoring 65%) and ROYBY. The other was a win on time by ROYBY, after the game had reached a drawn Bishops-of-opposite-colors endgame.

The JGD can lead to quiter play than the main lines, but White is in less of a hurry, as he has the advantage in material. 

Petasluk - ROYBY
5 0 blitz, FICS, 2017

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 


4...Kf8 

The Jerome Gambit Declined. Even though White has scored only 55% against it in the games in The Database, I cannot recommend it for Black. The defender gives up the opportunity of being two pieces up (with an insecure King) to be one pawn down (with an insecure King).

5.Bxg8 

Of course, White could also have withdrawn the Bishop.

5...Kxg8 6.c3 h6 7.d4 exd4 8.cxd4 Bb6 


A pleasant, if somewhat unsual position for the Jerome Gambit player - better pawn center, safer King, and ahead in material.

9.O-O Qe7 10.Re1 d6 11.Qb3+ Qf7 12.d5 Na5 


Removing the Knight from danger and attacking the enemy Queen - all in one move. But, seriously, folks, the stronger idea was 12...Ne5.

13.Qd3 Bd7 

Intentionally or not, Black abandons his Knight. He could have tried 13...c5, after which 14.dxc6 Nxc6 15.Qxd6 would net a pawn for White.

Interestingly enough, Stockfish 8 would prefer to ignore the offside Knight, and answer 13...c5 with 14.Nbd2!? Bc7 15.b3 Qg6 16.Bb2 Bd8 17.Qc3 b5 18.e5 b4 19.Qc1 Bh3 20.g3 Be7 21.exd6 Bxd6 22.Ne4 Qf7 23.Qe3 Nb7 24.Rad1 Rc8 25.Nxd6 Nxd6 when White has better development and Black's semi-castled King blocks one of his Rooks. Quite an improvement over the days when computers were pawn grabbers! 

14.b4 a6 15.bxa5 Bxa5 16.Bd2 Bb5 17.Qe3 Bb6 18.Qc3 Kh7 19.a4 Bd7 20.Be3 c5 


Black's c-pawn comes to the rescue of his Bishop, but probably simpler - if annoying, as it is not always the first choice to exchange pieces when you are behind in material - was 20...Bxe3.

21.dxc6 Rac8 22.Bxb6 Rxc6 23.Qb2 Bg4 24.Nbd2 Rf8 


Black has all of his pieces developed, but there are not enough of them.

25.Rac1 Bd7 26.Rxc6 Bxc6 27.Qc2 Kh8 28.Qd3 Qe7 29.Nd4 Bxa4 30.Nf5 

A slip that neither player notices: the Knight is not protected. White's e-pawn is effectively pinned, as 30...Rxf5 31.exf5? Qxe1 would be checkmate. If White didn't panic, he could still be better after 30...Rxf5 31.Nc4.

30...Qe5 31.Nxd6 

Clearly good enough to win. The ever-watchful Stockfish 8 suggests the very aggressive alternative, 31.Bd4!?, which both attacks the Black Queen and, through it, Black's Kingside. One possible outcome is 31...Bb5 32.Qa3 and White has too many threats.

31...Bc6 32.Nf3 Rf4 

A final slip, perhaps due to the clock. 

33.Nxe5 Black resigned


Wednesday, November 22, 2017

Jerome Gambit: Give Me A Break

I have maintained The Database of Jerome Gambit games to help me get a sense of how certain lines or moves succeed or fail - from a practical (i.e. over-the-board play) point of view.

I have used chess analysis engines (currently Stockfish 8) to get a sense of how certain lines or moves are "objectively" strong or weak.

It is a joy when both the practical and the analytical agree. It can be confusing when they don't. Take the following game. It left me a bit confused...

Petasluk - givemeabreak
5 0 blitz, FICS, 2017

1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+ 



4...Kxf7 5.Nxe5+ Nxe5 6.Qh5+ Kf6 



Including this game, Petasluk has reached this position 7 times according to The Database (which, I admit, need some updating). Before this game he was 2-1 with the followup 7.Qf5+ and 2-1 with 7.f4. This compares with statistics from the whole Database - White scores 80% (35 games) with 7.Qf5+ and 80% (10 games) with 7.f4.

So, from a practical point of view, 7.Qf5+ and 7.f4 are both good move choices, according to Petasluk's experience; and both are excellent choices from the experience of those represented by The Database.

7.f4 

So, no surprise here.

Yet the computer analysts, starting with Stockfish 8, leap directly for the straightforward 7.Qf5+ Ke7 8.Qxe5+ Kf8 9.Qxc5+ picking up the two sacrificed pieces.

Why the discrepancy?

7...g6

Well, here is one reason: the defender in this game is human, and humans make mistakes. The alternative 7...Nc6, withdrawing the attacked piece, allows White to only recover one of his sacrificed pieces:  8.Qf5+ Ke7 9.Qxc5+ Kf7, with pressure on the enemy King, but not full compensation for his offerings.

8.Qxe5+ Kf7 9.Qxh8 Black resigned 



Well, it looks like "Practical Experience 1, Computer Analysis 0".

But that is not the whole story. A number of Petasluk's games continued from the above "final" position:

9...Nf6 (9...d6 10.Qxh7+ Kf8 11.d3 Qf6 12.Qxc7 Be3 13.Nc3 Qxf4 14.Rf1 Qxf1+ 15.Kxf1 Bxc1 16.Rxc1 Black resigned, Petasluk - douthy, FICS, 2015; or 9...Qe7 10.Qxh7+ Kf6 11.Qxg8 Qxe4+ 12. Kd1 d5 13.Qh8+ Kf5 14.Qh3+ Kxf4 15.Rf1+ Kg5 16.Qg3+ Bg4+ 17. Rf3 Re8 18.c3 d4 19.h3 Qe2+ 20.Kc2 d3+ 21.Rxd3 Qd1 checkmate, Petasluk - kosten, FICS, 2013) 10.Qxd8 Black resigned Petasluk - skaks, FICS, 2015 and Petasluk - kaliz, blitz, FICS, 2014 Be7 11. Qh8 11... b6 12. e5 Bb7 13.Qxa8 Bxa8 14. exf6 Bxf6 15. O-O Be4 16. d3 Bc6 17. Nc3 Black resigned, Petasluk - TaccyChan, FICS, 2007.

That's 4 wins and 1 draw. More support for practical considerations.

But I expect the "Wait 'til next time!" bunch will want to look closer at 7.Qf5+.

(Where did the "extra" games come from? Petasluk - TaccyChan, FICS, 20017; Petasluk - Kosten, 2013 and Petasluk - douthy, FICS, 2015; all transposed from 6...Ke6.)