Michael Thompson made the first move on day four of the Honda Classic at Palm Beach Gardens to move clear of playing partner Luke Guthrie.
The two shared the third-round lead on eight under par but while Thompson improved his score by two, Guthrie was one over for the first six holes of his final round.
Thompson saw a long birdie putt at the second just dive left but opened up a three-stroke lead inside the first five holes, sparked when he drained a stunning long eagle putt at the third.
He dropped a shot at the next but birdied the par-three fifth to return to 10 under, while playing partner Guthrie squandered a birdie at the third with bogeys at two and five.
Both parred the next but Lee Westwood and Geoff Ogilvie, who started two shots behind the pair, had made no headway by that stage.
Westwood birdied the third but bogeyed the fifth and sixth while Ogilvie parred his first six holes to remain six under for the tournament.
Indeed, the only momentum among the chasing pack belonged to Erik Compton, who was two under for his front nine to catch Westwood on five under par and in a three-way tie for third. Alongside them was Graham DeLaet, who was one under through nine.
