Lessons From Cap Negret II

THE modern main line of the Exchange Variation of the Spanish starts 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Bxc6 dxc6 5.0-0 Bg4.

Position after 5...Bg4

Castling by White on move five goes back to at least 1867, but only became popular after it was taken up by Bobby Fischer.

His early games with it elicited the reply 5...f6, but that has been overtaken in usage by the pinning bishop move.

My round-two game, where I had white against Alonso Infante Martín (1556), began 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Bxc6 dxc6 5.d4.

Emanuel Lasker helped popularise 5.d4, although, at least according to ChessBase's 2026 Mega database, he played 5.Nc3 slightly more often.

The position after 5.d4 occurs 5,222 times in Mega26

In 4,822 of those games, Black continued with 5...exd4, but my game saw 5...Bg4!?

After the further moves 6.dxe5 Qxd1+ 7.Kxd1 0-0-0+ 8.Ke2 Bc5?! 9.Be3 Bxe3 10.Kxe3 White is a pawn up, and Black no longer has the bishop-pair as compensation for having a queenside pawn-majority that cannot make a passed pawn with normal play.

Stockfish17.1 and Dragon1 reckon White has a winning advantage.

I do not know why my opponent played 5...Bg4!?, but I suspect he was playing by analogy, knowing it was a sound move against 5.0-0 and thinking it must be right against 5.d4 too.

As a matter of fact, as I pointed out in my blog notes, 5...Bg4!? is playable, but Black must have one of two plans in mind.

Historically, the first plan was to make the game a definite gambit with 8...f6!? (instead of 8...Bc5?!). After 9.exf6!? Nxf6 10.Nc3 Bb4 11.h3 Bh5 12.g4 Bg6 13.e5 Nd7 Black had excellent compensation for a pawn in Kornél Havasi - Alexandru Tyroler, Hungarian Championship (Temesvár - now Timișoara, Romania) 1912, with Black going on to win in 28 moves.

The second plan, apparently introduced by Siegbert Tarrasch against Walter John at the 1914 German Chess Federation Congress at Mannheim, was to immediately go after White's extra pawn with 8...Re8.

That game continued 9.h3 Bxf3 10.Kxf3 Rxe5, with an equal game, according to Stockfish17.1 and Dragon1, although White went on to win in 36 moves.

However, the point is that Black more-or-less must adopt one of those two plans (make the game an out-and-out gambit, or fight to win back the pawn); merely getting on with development is unlikely to be enough.

LESSON: similar positions sometimes require similar plans, but you cannot just play by analogy as there will be occasions when, as in the two lines of the Spanish Exchange given above, an apparently small difference (5.d4 instead of 5.0-0) has a big effect.