[Event "USSR Championship, Moscow"] [Site "masterchessopen.com"] [Round "0"] [White "Bronstein, D."] [Black "Geller, E."] [Result "1-0"] [ECO "E20"] [Opening "Nimzo-Indian Defence"] 1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.a3 Bxc3+ 5.bxc3 O-O 6.f3 d5 7.cxd5 exd5 8.e3 Bf5 9.Ne2 Nbd7 10.Nf4 c5 11.Bd3 Bxd3 12.Qxd3 Re8 13.O-O Rc8 14.Rb1 Qa5 15.Rxb7 Nb6 16.g4 h6 17.h4 cxd4 18.g5 dxe3 19.gxf6 Rxc3 20.Qg6 { . A powerful blow, and one of my favourite puzzles because it is always stunning to sacrifice the queen in pursuit of checkmate. } ( { Black resigned, since the only way to stop 21 Qxg7 checkmate is to play } 20.Qg6 fxg6 { allowing } 21.Rxg7+ Kh8 ( { or } 21...Kf8 ) 22.Nxg6# { . } ) 1-0