Kirk played the final 36 holes with Rory McIlroy and outplayed the world's No. 1 player. Of far greater importance was winning this FedEx Cup playoff event, and he got it done with a bogey-free final round.
Billy Horschel had a chance to force a playoff by making a birdie on the par-5 18th. But he chunked his second shot so badly that it barely reached the hazard.
Kirk won for the second time this season. He won by two shots over Horschel, Russell Henley and Geoff Ogilvy.
U.S. captain Tom Watson announces his three wild-card selections on Tuesday in New York.
