Ruy Lopez Blue chess computer in Game 2 of their 1997 match. Svetozar Gligorić has been the most prolific C93 player. 9...Qd7 is another variation by Smyslov. Of the variations in this section, the Berlin and Schliemann Defences are the most popular today, followed by the Classical Defence. and other less-common third moves for Black. The Cozio Defence (part of "ECO" C60), 3...Nge7, is distinctly old-fashioned and the least popular of the defences at Black's third move. Although Bent Larsen used it occasionally with success, it remains one of the least explored variations of the Ruy Lopez. The Smyslov Defence, Fianchetto Defence,
Ruy Lopez especially if Black plays ...Bb7. White usually plays 9.h3 instead of 9.d4 (the Yates Variation) because after 9.d4 Bg4 (the Bogoljubow Variation), the pin of the white is troublesome. The variation takes its name from the game Capablanca–Bogoljubow, London 1922. The Chigorin Variation was refined by Mikhail Chigorin around the turn of the 20th century and became the primary Black defence to the Ruy Lopez for more than fifty years. With 9...Na5 Black chases the white bishop from the a2–g8 diagonal and frees the c-pawn for queenside expansion. After 10.Bc2 c5 11.d4 the classical Black follow up is 11...Qc7, reinforcing