Kelly, who had hit a 21-foot putt to get his round started on the second, sent the gallery roaring by making it. Then Potter missed his potential tournament-winner.
"Just got it outside the hole and hit it a touch harder than I wanted to, but I guess that's part of nerves there," Potter said.
Potter regrouped on the 18th, hitting his tee shot on the 164-yard par-3 within 5 feet. Kelly was 46 feet away, on the wrong side of the horseshoe-shaped hump in that unusual green.
Kelly gave it a good run, but to no avail. Potter made his putt look simple, beating the rumbles of thunder that could have delayed play.
The result gave both players a huge boost in what had been difficult seasons. Potter shot up to 51st in the FedExCup points list and should rise sharply from 218th in the Official World Golf Ranking.
His highest finish had been a 13th at the Sony Open, and he had made less than $200,000 this season.
Kelly rose from 239th to 104th in the FedExCup list - 125 is a magic number there. He has made just four cuts in 16 attempts, and had barely made $25,000. Sunday, he won $658,800.
But Potter gets the big trophy, capturing an event with a number of big names. Like Stallings before, he has come out of nowhere to put his stamp on the game of golf, at least for a few days.
Hey, he trended on Twitter after the tournament.
"Just knowing I've got a couple more years out here to have full exemption, to be able to play what I want to play in and be able to schedule my own tournaments, that's going to be nice," he said. "So I'm looking forward to that."
Reach Doug Smock at 304-348-5130, dougsm...@wvgazette.com or follow him at twitter.com/dougsmock.