23 f2-f3! Bb7xf3?? lines up with Black f7-king for pin Rc1-f1 Rubinstein vs Alekhine, 1922  (D94) Grunfeld, 26 moves, 1-0 Y Shulman vs Kamsky, 2010  (D11) Queen's Gambit Declined Slav, 66 moves, 1/2-1/2 36 ... Qe8-d7?! aligns with c8-rook, 37 Bb6-c7! is sq clearance T Sachdev vs J W de Jong, 2011  (D39) Queen's Gambit Declined, Ragozin, Vienna Variation, 46 moves, 1-0 Fischer vs E Stepans, 1957  (B77) Sicilian, Dragon, Yugoslav Attack, 25 moves, 1-0