Ruy Lopez 5.d4 exd4 6.Qxd4 and White is in . After 4...dxc6, the obvious 5.Nxe5 is weak, since 5...Qd4 6.Nf3 Qxe4+ 7.Qe2 Qxe2+ leaves White with no compensation for Black's bishop pair. There are two principal lines after 4.Bxc6 dxc6. In the late 19th and early 20th centuries, Lasker had great success with 5.d4 exd4 6.Qxd4 Qxd4 7.Nxd4. Since then, better defences for Black have been developed, and this line is considered to slightly favour Black. Jon Jacobs wrote in the July 2005 "Chess Life" (p. 21): "A database search (limited to games longer than 20 moves, both players FIDE 2300+) reveals
Ruy Lopez, Noah's Ark Trap and José Capablanca at the Budapest tournament in 1929: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 d6 5. d4 5... b5 6. Bb3 Nxd4 7. Nxd4 exd4 8. Qxd4?? 8... c5 9. Qd5 Be6 10. Qc6+ Bd7 11. Qd5 c4 (see diagram) A variation of this trap can occur in the Sicilian Defense after the moves 1.e4 c5 2.Nf3 Nc6 3.Bb5 (the Rossolimo Variation) a6 4.Ba4?? (4.Bxc6 is necessary and the point of 3.Bb5 itself) b5 5.Bb3 c4 (see diagram) and the bishop is similarly trapped. Bibliography Ruy Lopez, Noah's Ark Trap The Noah's Ark Trap