[White "   Keres - Petrov, 1940   "]   [Black "White to play and win"]   [Result "1-0"]   [FEN "r1b3k1/ppp2r2/6p1/3n3p/6qP/3BQ3/PBP5/2KR3R w - - 0 1"]   {In the diagram position, Keres found the brilliant}   1 Bc4!!   {Whatever Black does, he is lost:}   1... c6 {most resilient}   (1... Nxe3 2 Rd8+ Kh7 3 Rh8 {mate})   (1... Qxc4 2 Qe8+ Rf8 3 Qxg6 {mate})   2 Rxd5! cxd5 3 Bxd5   {Here Black is busted. For instance}  3... Bf5    ({or} 3...Kf8 4 Qh6+) 4 Qe5