protecting isolated pawns on c3 a3 A Hahn vs V Gaprindashvili, 2000 (E47) Nimzo-Indian, 4.e3 O-O 5.Bd3, 46 moves, 0-1 Queen's gambit accepted Euwe vs Gruenfeld, 1936 (D28) Queen's Gambit Accepted, Classical, 28 moves, 1-0 Man Vs. Machine Deep Junior vs Kasparov, 2003  (B44) Sicilian, 61 moves, 1/2-1/2 Sicilian Kramnik vs Anand, 2004  (B92) Sicilian, Najdorf, Opocensky Variation, 25 moves, 1/2-1/2 Na3 wild game G Minchev vs O Santana, 1987  (A00) Uncommon Opening, 76 moves, 1-0 5 games