Rory McIlroy won the fourth major of his already-impressive career after digging deep to edge a gripping US PGA Championship at a rainy Valhalla.
World number one McIlroy, 25, saw his overnight one-shot lead wiped out on the front nine before taking control after the turn to win by one shot.
A three-under 68 on the final day saw off Phil Mickelson, with Rickie Fowler and Henrik Stenson another shot adrift.
The Open champion won successive majors with an overall total of 16 under par.
The Northern Irishman is the third youngest player after Tiger Woods and Jack Nicklaus to win four of golf's biggest prizes, while he also becomes the first man to win back-to-back majors since Padraig Harrington in 2008.
McIlroy's resurgence on the back nine capped an enthralling final day - delayed for almost two hours after a heavy downpour - where the identity of the winner could not be predicted until a dramatic conclusion.