Former world No.2 Jim Furyk grabbed his 14th US Tour victory, but first since 2007, when he won the Transitions Championship by one shot from Korean KJ Choi in Florida.
After a thunderstorm delay of almost four hours the 39-year-old American scored a last round 69, two under par, over the Copperhead course at Palm Harbor's Innisbrook Resort.
Nick O'hern was the best placed Australian in a tie for eighth place, seven shots behind Furyk.
Greg Chalmers (T16), James Nitties (T20), Steve Elkington (T25) and Adam Scott (T28) all finished strongly, but Geoff Ogilvy and John Senden both had disappointing rounds of 74 of 76 respectively to drop down the leaderboard into a tie for 28th place.
Four birdies in five holes from the second by twice winner Choi cancelled out Furyk's three-stroke overnight lead, but the 2003 US Open champion responded in fine fashion.
With birdies of his own at the eighth, 10th and 12th he was three clear again.
Another birdie came at the long 14th, but either side of that came bogey fours to leave him two in front and he had to work hard for pars on the 16th and 17th.
That enabled him to make bogey after a near shank from the trees on the last and still win with a 13 under aggregate of 269.
Luke Donald's 71 put him in a tie for sixth, while Padraig Harrington, the halfway leader, climbed back to joint second with an opening birdie, but fell back to joint eighth on six under after a 72.
Furyk did end last year with a victory at the Chevron World Challenge, but that is not an official Tour stop and he had said: "I want to win an event out here on the PGA Tour."
Furyk admitted: "Nerves got me, to be honest with you. I have a habit of making it tough for myself.
"The only time I haven't was the US Open."