To use Morphy’s mating pattern a sacrifice often is needed to get the g-file all the way open—as is the case here. White has no way to capture the g7 pawn, but we know more than one way to clear a bothersome pawn out of the way: take something it protects. Then a rook check on the g-file will drive the king into the corner and the bishop can add the finishing touch. To be more precise: 1. QxN, requiring g7xQ (otherwise White mates with Qxg7); then 2. Rg1+, Kh8; 3. Bxf6#. The end position is the same as in the previous diagram, but with White’s bishop advanced to f6—and since the bishop is right in front of the f7 pawn, there is no danger of Black interposing anything. The sacrifice on f6 to open the g-file illustrated here, with mate then delivered roughly as shown, is the specific idea known as Morphy’s mate.