Chesson Hadley posted a 1-under 69 on Sunday and won the Web.com Tour Championships by two strokes.
Hadley, who won for the second time this season on the Web.com Tour, finished at 10-under-par 270. He finished second on the Web.com Finals Series money list, but still earned his PGA Tour card for the 2013-14 season.
"This is incredible. I have no idea ... it was just black-out golf all out there today. I was just trying not puke on myself on the way in," Hadley admitted. "I'm so thrilled. This course is brutal, I'm just glad I conquered it."
John Peterson closed with a 67 to gain a share of second place at minus-8. Peterson finished inside the top 10 at all four Finals Series events and finished atop that money list.
"At the end of the day, he played the best out of everybody in the four tournaments. Shoot, he's played the best golf the past five or six tournaments," Hadley said of Peterson. "Congrats to John Peterson. I'm happy for him, that's great."
Peterson and Michael Putnam, who finished atop the regular season money list, have fully exempt status for next season on the PGA Tour and will be invited to the Players Championship.
Brad Fritsch (66), Scott Gardiner (72) and Brendon Todd (65) shared second place with Peterson at minus-8.
Russell Knox and Andrew Loupe both closed with 1-under 69s to share sixth place at 7-under 273 on the Dye's Valley Course at TPC Sawgrass.
Lee Williams poured in a birdie effort from outside 50 feet on the 18th green for a round of 69. That gave him a share of eighth at minus-6, and enough money to earn his PGA Tour card for 2013-14.
"My caddie told me after I hit my second shot that 6-under gets in. So I knew I needed to make that putt on 18," Williams stated. "I was just trying to simplify the putt, because it was not an easy putt. I just wanted to make sure it got to the hole so I gave myself a chance."
Earlier Sunday, there was a weather delay that forced officials to change the groupings to threesomes off the first and 10th tees. That put Hadley in a group with third-round leader Gardiner and Joe Durant.
Hadley got off to a fast start with birdies on the first, third and fifth. That spurt moved him to 12-under, where he was three clear of Knox, Gardiner and Peterson.
After four pars in a row, Hadley stumbled to a bogey on the 10th and that trimmed his lead to two over Fritsch and Knox. Hadley traded a birdie for a bogey from the 12th.
Hadley stumbled to another bogey at the 15th, but still led by two over six players.
Gardiner, who played the front nine in 3-over par with a bogey, two birdies and two double-bogeys, rolled in a 5-footer for eagle on the par-5 16th to briefly move within one of Hadley's lead.
Hadley birdied the same hole from three feet to push his margin back to two. Both players stumbled to bogeys at the 17th. Hadley, who lost the third-round lead with a double-bogey on the 18th on Saturday, closed with a par to seal the victory.
NOTES: Hadley earned $180,000 for the victory ... Fourteen of the 25 players that earned their PGA Tour cards for 2013-14 through the Finals Series were PGA Tour players, who were able to keep their tour cards. The other 11 were Web.com players that move on to PGA Tour next season ... Among the 50 players that got their cards for next year were Trevor Immelman, Will Mackenzie, Ryo Ishikawa, Sean O'Hair, Knox, Chad Collins, Durant, Ricky Barnes and Daniel Chopra.