Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bb5/3...f5/4. Nc3/4...fxe4/5. Nxe4

Ruy Lopez, Schliemann Defence

	a	b	c	d	e	f	g	h
8									8
7									7
6									6
5									5
4									4
3									3
2									2
1									1
	a	b	c	d	e	f	g	h

Common moves:
5...d5 - Old Main Line
5...Nf6 - Tartakower Variation

Black may now accept the invitation to build a classical pawn centre with 5...d5. If White were forced to retreat the e4-knight, this would be enough to put 4.Nc3 out of business. Alas, Black players at GM level have been scoring very badly out of the well-analysed complications that follow White's critical reply 6.Nxe5!

So Schliemann Defence champion Teimour Radjabov prefers the more sedate 5...Nf6, with the character of the resulting positions depending on whether White now exchanges on f6 voluntarily or has to be forced into it with 6.Qe2 d5.

Wikipedia has related information at Ruy Lopez