Ruy Lopez 8...Na5 by playing 8.a3 (8.c3 or 8 a4 are perfectly playable as well) and after 8...0-0 (the immediate 8...Na5 is also feasible) 9.Nc3 we have reached a modern tabiya of the Ruy Lopez. This position was first reached in a high-level encounter between Viswanathan Anand and Michael Adams, Grenke Chess Classic 2013. 6.d3 has gained wide popularity among the top players and has almost supplanted the Ruy Lopez main line with 6.Re1. Peter Svidler has dedicated an entire video series to the fashionable 6.d3 line. In the Averbakh Variation (C87), named for Yuri Averbakh, Black defends the threatened e-pawn with
Ruy Lopez, Exchange Variation than this. White now threatens 6.Nxe5 because the sequence 6...Qd4 7.Nf3 Qxe4 to regain the pawn, now fails to 8.Re1 pinning and winning the queen. "ECO" code C68 examines these responses to 5.0-0: 5...Qf6, 5...Qe7, 5...Bd6, 5...Qd6, or 5...Bg4 (all directly defending the e5-pawn, except 5...Bg4 which indirectly defends by pinning the knight). The moves 5...Be6, 5...Be7, and 5...Ne7 are less common moves which have never achieved popularity. The idea behind these moves is that if White plays to win a pawn with 6.Nxe5, 6...Qd4 7.Nf3 Qxe4 is again playable, as the Black minor piece on e6 or e7 blocks