Ruy Lopez, Exchange Variation Ruy Lopez, Exchange Variation The Exchange Variation of the Ruy Lopez is a chess opening that begins with the moves: Black may recapture on c6 with either pawn; although 4...bxc6 is playable, 4...dxc6 is almost always chosen at master level. Black has gained the at the cost of a weakened pawn structure, due to his doubled pawns on c6 and c7. White aims to reach an endgame in which he has the superior pawn structure, which may become an important factor. Thus, Black is compelled to strive for an active position, generally avoiding piece exchanges. The variation was introduced into
Ruy Lopez Morphy, and it is named for him. Steinitz did not approve of the move; in 1889, he wrote, "on principle this ought to be disadvantageous as it drives the bishop where it wants to go". Steinitz's opinion did not prevail, however; today, 3...a6 is played in over 65 percent of all games beginning with the Ruy Lopez. After 3...a6, the most commonly played line is the Closed Defence, which goes 4.Ba4 Nf6 5.0-0 Be7, discussed in the two following sections. Alternatives to the Closed Defence described in this section are: In the Exchange Variation, 4.Bxc6, ("ECO" C68–C69) White damages Black's