Rory Sabbatini held off a final-round charge from YE Yang to close out his sixth PGA Tour victory at the Honda Classic.
The South African was under pressure as his overnight five-shot lead was whittled down to just one when playing partner Yang birdied the 15th.
But Sabbatini, who had opened the door with a three-putt bogey at the 14th, responded in kind at the next to restore his two-shot cushion.
Both men found the green with their tee shot to the par-three 17th before play was suspended for 28 minutes to allow a storm to pass through the PGA National Champion Course in Palm Beach Gardens.
Sabbatini returned to par the final two holes and complete his first win for almost two years.
His level-par 70 on Sunday gave him a nine-under-par total for the week, one better than 2009 winner Yang, who birdied the 18th to complete a four-under 66.
"I'm just beside myself," said a tearful Sabbatini, who underwent surgery for skin cancer three months ago.
The 34-year-old's wife, Amy, also had a stay in intensive care after a difficult childbirth and Sabbatini added: "There is a lot that has occurred since my last win and it's just fantastic to be here again."
American Jerry Kelly birdied the final two holes in a 67 to take third place at seven under.
Kelly's compatriot Ricky Barnes was alone in fourth at four under after a 67 and Tommy Gainey's 68 saw him end up one further back in fifth.
Earlier, US Open champion Graeme McDowell equalled Sabbatini's two-day-old course record with a six-under 64 that moved him up from 30th to joint sixth on two under.
After turning in 33 the Northern Irishman holed from almost 45 feet at the 11th, added another birdie on the 13th and then finished with two more.
McDowell, who sank a 35 footer at the short 17th and then was on in two at the last, said: "It was a very different golf course today.
"The wind had switched and the 'Bear Trap' was a lot more civilised."
He will stay fourth in the world rankings, though, because last week's World Match Play winner Luke Donald was only a stroke behind him following a bogey-free 66.
Lee Westwood had required a top three placing to regain top spot on the rankings from the resting Martin Kaymer, but that was never on long before he double-bogeyed the 17th.
Round in 70, Westwood finished four-over-par, while Ian Poulter (67) was five over and Rory McIlroy, who closed with scores of 77 and 75, was down on 16 over.
They all now head to Miami for this week's WGC-Cadillac Championship. The event won by Ernie Els last year will see Tiger Woods' fourth appearance of the season.
Sabbatini, up now from 102nd in the world to just outside the top 50, has qualified by climbing into the top 10 on the PGA Tour's FedEx Cup standings.