Sicilian Defence, Katalymov Variation GM Christian Bauer, with which he managed to draw a game in 2005 against currently top-ranked GM Magnus Carlsen. It has also been used by top players such as Gata Kamsky and Soviet GM Lev Psakhis. The opening is named after Soviet IM Boris Katalymov (1932–2013). Bibliography Sicilian Defence, Katalymov Variation In chess, the Katalymov Variation (also spelled Katalimov) is a less popular line of the Sicilian Defence that begins with the moves: The Katalymov is considered inferior since it commits Black to a plan with ...b6 rather than more aggressive Sicilian defences incorporating b7–b5. Black must protect the b5-square,
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