Atlanta - Jordan Spieth capped an epic season with a Tour Championship victory that boosted him back to number one in the world and took his 2015 winnings to more than $22 million.
The 22-year-old Texan, whose five wins this season included the Masters and US Open, fired a final round 69 for 271 and a four-shot win over Sweden's Henrik Stenson, New Zealand's Danny Lee and England's Justin Rose.
With the win - and Jason Day's 10th-place finish - Spieth will recapture the number one ranking Australia's Day had held for a week.
He also set a US PGA Tour record for earnings, the Tour Championship first prize of $1.485 million taking his total for the year to $12 030 465 - not including the $10 million bonus that came with his FedEx Cup playoff title.
"This year is unreal," said Spieth, who in addition to his two major victories finished tied for fourth at the British Open and runner-up to Day at the PGA Championship.
"I don't know how we sit down and figure out how to improve on it, but we're going to try and do that."
Spieth also won the US Tour's Valspar Championship and John Deere Classic - but admitted he was stung by back-to-back missed cuts in the first two events of the US Tour's elite four tournament playoff series.
"I got mad," said Spieth, who responded by preparing for the Tour Championship as if it was a major.
"I didn't have a great playoffs, but I put a lot into this week. Mentally I stayed in it, and boy, that putter sure paid off."
Day had come on strong at the end of the season, but with this win Spieth dampened any debate about who would deserve Player of the Year honours.
Spieth started the day with a one-stroke lead over Stenson, and the Swede - who could also have seized the playoff bonus with a victory - tried to keep the pressure on.
Back to back bogeys from Spieth at the fifth and sixth saw Stenson pull level, but Spieth was just too good on the greens.
He poured in a 21-foot birdie putt at the eighth as Stenson bogeyed to restore his two-shot cushion.
He drained an 18-footer at the ninth - to maintain his advantage despite Stenson's birdie, and bounced back from a bogey at 10 with a 47-foot birdie putt at the 11th.
The rest of the way Spieth found the clutch par putts when he needed them. That included a nine-footer at the 15th and a putt of about the same distance at 16.
Stenson, meanwhile, found his race for the title turning into a battle to hang on to at least a share of second, which he relinquished with a double-bogey at 17.
But Stenson rolled in a long birdie putt at the par-three 18th to cap a two-over 72 that was good enough to join Lee and Rose on five-under, Lee climbing up the leader board with a five-under 65 and Rose signing for a 66.
As at the Masters in April, Stenson said he could only admire Spieth's display.
"It's been a phenomenal year for him," Stenson said. "I watched it first hand at the first two rounds at Augusta and he played phenomenal and putted phenomenal.
"It was the same putting display today - just an exhibition on the greens to be honest."
Day closed his tournament with a 68 for a share of 10th. His five wins this season included not only his breakthrough major at the PGA but also two playoff tournaments, but he finished third in the FedEx Cup final standings behind Spieth and Stenson.
"I could have played better this week," Day said as Spieth was powering toward the finish line. "But it just seems like Jordan is kind of zoned in and grinding for that win."
Final-round scores on Sunday in the $8.25 million US PGA Tour Championship, final event in the FedEx Cup playoff series (USA unless noted, par 70):
271 - Jordan Spieth 68-66-68-69
275 - Henrik Stenson (SWE) 63-68-72-72, Danny Lee (NZL) 69-72-69-65, Justin Rose (ENG) 70-68-71-66
276 - Dustin Johnson 69-72-71-64, Bubba Watson 70-71-68-67, Paul Casey (ENG) 65-70-71-70
277 - J.B. Holmes 68-72-68-69, Zach Johnson 66-70-71-70
278 - Matt Kuchar 71-70-69-68, Jason Day (AUS) 69-71-70-68
280 - Steven Bowditch (AUS) 68-69-73-70, Hideki Matsuyama (JPN) 69-72-69-70, Daniel Berger 69-73-68-70, Rickie Fowler 69-70-67-74
281 - Kevin Na 68-73-70-70, Rory McIlroy (NIR) 66-71-70-74
284 - Robert Streb 75-75-69-65, Jimmy Walker 73-71-74-66, Bae Sang-Moon, 73-70-72-69, Brooks Koepka 68-74-72-70
285 - Harris English 71-76-71-67, Brandt Snedeker 68-72-75-70, Charley Hoffman 73-72-70-70
290 - Scott Piercy 74-73-73-70
293 - Bill Haas 72-73-72-76
294 - Patrick Reed 72-74-77-71
298 - Kevin Kisner 76-77-72-73
WD -- Louis Oosthuizen (RSA)
DNS -- Jim Furyk