C42 · Petrov's Defense Petrov's Defense: Nimzowitsch Attack Línea reconocida: e4 e5 Nf3 Nf6 Nxe5 d6 Nf3 Nxe4 Nc3 e4e5Nf3Nf6Nxe5d6Nf3Nxe4Nc3