Figure[White to move]

Last, a sequence that involves clearing a path to create a discovered check. Start by spotting the kernel of a discovery for White on the g-file: anytime you have a rook with a friendly piece in front of it, take notice. Here the idea is especially appealing because Black’s king is on the same file. Ask what stands between White and a discovered check. Answer: only the g6 pawn. How do you force a pawn to move? By capturing something it protects. The g6 pawn protects the queen, so White plays QxQ; after Black replies g6xQ, the path on the g-file is clear for the discovered check—indeed, the double check—Ne6++. After Black moves his king (the only possible reply to a double check), White has NxR. Black recaptures and White has won the exchange.