(Reuters) - American Bill Haas broke free with a back nine surge and posted a three-stroke victory at the AT&T National at Congressional Country Club in Bethesda, Maryland on Sunday.
Haas began a muggy final round in a four-way tie atop the leaderboard with fellow Americans Roberto Castro and James Driscoll and Andres Romero of Argentina.
He pulled away with three straight birdies from the eighth and two more at the 14th and 16th for a five-under 66.
"I just kept the ball in front of me," said Haas, who had missed the cut in three of his four previous PGA Tour events. "Nothing too crazy."
Castro opened his round with a bogey at the first but was error free the rest of the day, returning a two-under 69 to finish three back of Haas, who collected his fifth career PGA Tour title with a four-day total of 12-under 272.
When Haas calmly rolled in a three-foot par putt at the 18th he joined Phil Mickelson, Dustin Johnson and Justin Rose as the only players to record at least one PGA Tour win in each of the last four seasons.
The 31-year-old was handed the trophy from tournament host Tiger Woods, who was unable to take part in the event because of an elbow injury that will keep the world number one out of action until the British Open.
"He played beautifully today," said Woods on the PGA Tour website. "He handled his business through the tougher stretch of holes and pulled away."
Long-hitting American Jason Kokrak (69) and South Korean Dong-Hwan Lee, with the round of the day at seven-under 64, finished in a tie for third one shot further adrift on eight-under.
Lee, chasing his first PGA Tour win, made a terrific charge with birdies on six of his opening eight holes, including five straight from the fourth.
Back-to-back bogeys at 10 and 11 took the steam out of Lee's challenge but still finished strong with three more birdies to return the best round of the week at the Congressional.
(Reporting by Steve Keating in Toronto; Editing by Gene Cherry/Ian Ransom)