Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bb5/3...a6/4. Bxc6/4...dxc6/5. d4

= Ruy Lopez: Exchange Variation = Against this move, Black should play /5...exd4/, as he shouldn't allow White to play Nxe5 or dxe5 which would favor White.

Theory table
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 * 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Bxc6 dxc6 5.d4