Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bb5/3...a6/4. Ba4/4...Nf6/5. O-O/5...Nxe4/6. Re1

=Ruy Lopez, Riga Variation= The best move here is Nc5. This leads to 7.Bxc6 dxc6 8.d4 Ne6 9.Nxe5 Be7 10.Be3 0-0 11.c4 Bf6 or 11.- Bd6 with an equal position.

Theory table
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'''1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. O-O Nxe4 6.Re1'''