Keegan Bradley, ranked 108th in the world, beat Jason Dufner in a three-hole play-off to win his first ever major at the US PGA.

The 25-year-old American triumphed by one shot over his fellow countryman over the extra holes after they had both finished level at eight under in Atlanta.

Incredibly, Bradley had triple-bogeyed the 15th, giving Dufner a five-shot lead with just three holes to play,  but fought back as his rival seemingly suffered an attack of nerves.

Top two in the world, Luke Donald and Lee Westwood both halved their six-shot deficits on Sunday but fell away towards the end to both finish on three under.

Bradley went into the final day one shot behind  Dufner and after a shaky start, an eagle on the 12th hole saw him join his compatriot at the top of the leaderboard on nine under.

However he then chipped through the green into the water on the 15th, before back-to-back birdies on the next two holes.

34-year-old Dufner also found water on the 15th, this time from the tee, and this  sparked a spectacular downfall, as his bogey on the same hole, plus two more on the 16th and 17th saw him drop back alongside Bradley.

In the play-off, Bradley birdied the first hole, the 16th, to Dufner’s par and then made par on the short 17th as Dufner once again bogied. Dufner birdied the 18th but Bradley’s par was enough to hand him the Wanamaker Trophy and become the first American to clinch a major title since Phil Mickelson won the Masters in 2010.