Charley Hoffman birdied four of his first five holes on Saturday as he opened up a two-shot lead ahead of the final round of the RBC Heritage at Hilton Head.
Tied for the lead overnight, Hoffman made a blistering start to his third round to pull clear of the field and then maintained his advantage as he posted a bogey-free 66.
That left him on 11-under-par by the close, two clear of Webb Simpson - who shot a superb 65 - and a further stroke clear of Kevin Streelman (69) with whom he shared the overnight lead.
Graeme McDowell (68) birdied the 18th to finish four off the pace in a tie for fourth with Zimbabwe's Brendon de Jonge, but Ryder Cup colleague Luke Donald saw his hopes fade after a level-par 71 left him six adrift.
But it's Hoffman who is in pole position to clinch his third PGA Tour victory - and a first for almost three years - as he built on a quite remarkable start to his round.
The 36-year-old got the ball rolling with a birdie at the first and then took advantage of the par-five second to push himself into the lead at eight-under.
After a par at the third, he rolled home a 12-footer for birdie at the par-three fourth hole and then nudged home from about half that distance to pick up another stroke at the long fifth.
That saw him open a three-shot lead over his rivals and he would go on to produce a couple of good escapes after wayward drives to keep a bogey off his card.
His sole birdie of the back-nine came at another par-five, the 15th, where he sunk an unlikely 40-footer across the green to edge further clear of a charging Simpson.
The US Open champion made three birdies on both the front and back nine as he roared into contention and also managed to go bogey-free around the tight and testing Harbour Town Golf Links.
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