
The Australian began the day six shots off the lead with a lot of players ahead of him, but on a roller-coaster day that saw the contenders drop away one after another, it was Scott who was left atop the leaderboard.
(US unless stated)
-11 A Scott (Aus)
-10 G Woodland
-10 G DeLaet (Can)
-10 T Woods
-10 J Rose (Eng)
Click here for collated scores
At one stage his final tally of 11 under par looked as though it would only be enough for a play-off at best, with Tiger Woods, Gary Woodland, Justin Rose and Kevin Chappell all in position to go one better throughout the afternoon.
Joint overnight leader Matt Kuchar endured the most dramatic implosion, a triple bogey at the ninth completely ruling him out of contention, eventually signing for an 78.
It meant it was all change at the top and starting out on the back nine it was Chappell who led by two after two birdies in three holes until he, too, capitulated with a three-put double-bogey at the 11th, and he gave back a further five shots on the way to a 76.
US Open champion Rose went down the final hole tied with Scott having made four birdies in an error-free round, but he raced his birdie putt four feet past and failed to make the one back to drop disappointingly out of the lead.
Woods was the next to make a last ditch attempt to join Scott at the top, despite a back spasm that clearly affected his swing throughout the back nine.
Having made it to -11, he dropped shots at the 10th, 13th and 15th and appeared to be drifting out of contention until a grandstand finish that saw him drain birdie putts and 16 and 17.
His approach to the last went through the green but his putt finished agonisingly short, meaning he too finished a shot shy of a play-off.
Woodland, who held the overnight lead with Kuchar, double-bogeyed the fifth but got a stroke back at the seventh to get back to the magical 11-under-par figure, however he bogeyed the 13th and then spurned very holeable putts at the last three greens to match Scott's score.
So it is the Masters champion who goes to the Deutsche Bank Championship in Boston next week in second place behind Woods in the FedEx Cup standings, with Phil Mickelson in third place.
Mickelson burned it up on Sunday, picking up six shots in eight holes midway through his round to come from way back and reach 10-under-par before dropping his only shot of the day at the last.
The top 100 in the standings head to Boston, some consolation for England's David Lynn, who started the day in contention but double-bogeyed the first in an outward 41, before picking up two shots coming home to finish alongside Kuchar and Rory McIlroy (72) on -5.

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