Patrick Reed held his nerve to triumph in the WGC-Cadillac Championship in Doral, Florida as Tiger Woods was unable to mount a challenge on the final day.
Reed appeared to be cruising to the biggest win of his career after taking a four-shot lead into the final nine holes before starting to struggle, with a bogey on the 15th leaving him just one clear of Welshman Jamie Donaldson.
However, Donaldson made his first bogey of the day on the last to give Reed some breathing room and the 23-year-old American managed to steady himself to record a one-shot victory.
Starting as overnight leader, Reed looked firmly on course for victory after opening up with three birdies in four holes, with a bogey on the par-four second taking him to six under par overall.
However, he would not make another birdie for the rest of the day, which left him hanging on for his third PGA Tour victory, having triumphed at the Wyndham Championship in August 2013 and the Humana Challenge earlier this year.
Reed began and finished the day on four under par overall, with compatriot Bubba Watson and Donaldson settling for a tie for second.
Woods eventually finished nine shots adrift of Reed after a disastrous final round 78, with his back injury clearly hampering his efforts.
The world number one was in contention after a superb six-under-par 66 on Saturday left him three shots adrift overnight.
Needing a strong start to have any chance of putting pressure on the frontrunners, Woods began with two pars but bogeys at the third and fourth undermined his challenge and another one at the sixth left him needing a miracle.
In the end, it was to the 38-year-old's credit that he managed to complete his round, as he came home in a tie for 25th.
Rory McIlroy had begun the weekend one shot off the lead, but the former world number one suffered a dismal final two rounds to finish five shots off the pace.
"I feel like I struck the ball well for the most part," McIlroy told the tournament's website. "On the greens I didn't get anything going with the putter and anytime I missed the green I didn't really get anything going."
The Northern Irishman admitted some frustrations at the Doral conditions.
"It's a frustrating golf course because you feel like you should be doing so much better, and it just doesn't allow you to," he said. "You have to be so precise and just to get the ball close on some of these greens and these pin positions. I don't know if it's because you've got memories of the course before, like going low, and the way it is now it just doesn't allow you to do that."
Reed credited hard work for his success.
"It means a lot to come out here and play as well as I did, with Tiger close to the lead and Hunter Mahan really close, Jason Dufner, all those great guys that are Major winners who have been on Ryder Cup teams," he said. "They are just outstanding players.
"I have a lot of confidence in my game. It's one of those things that you build confidence by how hard you work, and I feel like I'm one of the hardest workers out here and it definitely shows."