Ruy Lopez: Morphy Defense, Mackenzie Variation

The Ruy Lopez: Morphy Defense, Mackenzie Variation is a chess opening classified under ECO code C77 in the Open Games & French Defense family, beginning with 1.e4 e5 or 1.e4 e6, including the Italian Game, Ruy Lopez, and French Defense. It is reached after 5 moves: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. d4. The resulting position leaves black to move.