Nürnberg Variation

The Nürnberg Variation, 3...f6, meets the Ruy Lopez by propping up e5 with the f-pawn. The extra support is superfluous, since e5 is not yet genuinely attacked, and it costs Black the natural f6 square for the king's knight while loosening the kingside. The move does set a trap. After 4. Bxc6 dxc6, the most frequent reply, the tempting 5. Nxe5 fxe5 6. Qh5+ fails to 6...Kd7 7. Qxe5 Qf6, when White faces a queen trade into an ending a bishop down for two pawns, and Black stands better. The analogous sacrifice that refutes the Damiano Defense, 1. e4 e5 2. Nf3 f6 3. Nxe5 fxe5 4. Qh5+, does not carry over here.

White does better to develop normally. After 4. O-O the idea is to open the center with d4; one line runs 4...a6 5. Bc4 Bc5 6. c3 Nge7 7. d4 b5 8. Bb3 exd4 9. cxd4 Bb6 10. Nc3, leaving White with more space and smoother development. Engines give White a slight edge, and White scores well in practice.