Ruy Lopez that after the common retreat 4.Ba4, Black will have the possibility of breaking a future pin on his by playing ...b5. White must take some care not to fall into the Ruy Lopez, Noah's Ark Trap, in which Black traps White's on the b3-square with a ...a6, ...b5, and ...c4 pawn advance on the . Ercole del Rio, in his 1750 treatise "Sopra il giuoco degli Scacchi, Osservazioni pratiche dell'anonimo Modenese" (On the game of Chess, practical Observations by an anonymous Modenese), was the first author to mention 3...a6. However, the move became popular after it was played by Paul
Libro de la invencion liberal y arte del juego del axedrez the second part, López introduces the word "gambit" and gives some openings that had not been previously published: the King's Gambit, some variations of the Bishop's Opening, and what is now known as the Steinitz Defense in the Ruy Lopez. The last two parts of the book are critical of the games of Damiano. After the moves 1.e4 e5 2.Nf3, Damiano thought that 2...Nc6 was Black's best move. López considered that inferior because of 3.Bb5. This opening is now known as the Ruy Lopez, although he did not invent it . Libro de la invencion liberal y arte del juego