Henrik Stenson led by nine shots in the middle of Saturday's third round. With four holes to go in Sunday's final round, that lead was down to one.
Stenson then birdied the 15th and cruised home with three straight pars to win The Tour Championship by three strokes. He shot 2-under 68 in the final round for his fourth straight round in the 60s.
The Swede finished his fourth PGA Tour title at 13-under-par 267. He also won the FedExCup, moving ahead of two-time FedExCup champion Tiger Woods.
Stenson became the first European to win the FedExCup and he was also the first European to win The Tour Championship.
"Since the Scottish Open, the week before the Open Championship, it has just been an incredible run. The results I produced, it was a tough day out there today. To hang in the way I did, I'm really satisfied," Stenson said at the trophy presentation.
Since the Scottish Open, Stenson has six top-three finishes, a share of 33rd and a tie for 43rd at the The Barclays.
Jordan Spieth fired a 6-under 64 for the second-best score of the day, despite a bogey at the 17th. That helped him jump into second place at minus-10. Spieth was joined there by Steve Stricker, who closed with a 65 at East Lake.
Webb Simpson had the low round of the day, a 7-under 63, which helped him grab fourth place at 9-under-par 271. Dustin Johnson birdied three of the last four holes, but wrapped them around a triple bogey at the 17th. He managed a 1- under 69 to end in fifth at minus-8.
U.S. Open champion Justin Rose carded a 3-under 67 to end in sixth at minus-7. Zach Johnson and Billy Horschel both closed with 68s to share seventh at 6- under 274.
Woods carded a 3-under 67 and shared 22nd at even-par 280.
Brandt Snedeker, last year's Tour Champion and FedExCup winner, shot 2-under 68 to tie Hunter Mahan for 20th at 1-under 279.
Stenson started the final round with six straight pars, but he was still four clear at that point. He stuffed his approach inside three feet at the seventh and knocked that in for his first birdie to move five clear of Spieth.
Spieth birdied the first, but gave that right back with a bogey at the second. He jumped to minus-7 with three straight birdies from the seventh.
Stenson answered with a birdie on No. 11 to again move four clear.
Spieth started his late charge with a birdie on No. 13. He followed birdies on the next three holes to jump within two.
Stenson missed the green at the 14th and that led to a bogey, which trimmed his lead to one.
That was followed by a two-stroke swing, as Spieth's approach buried in a bunker at No. 17. He blasted to 18 feet and 2-putted for bogey to slide two behind. Meanwhile, Stenson chipped his third at the par-5 15th to seven feet and he drained that for birdie to push his advantage to three strokes.
Spieth parred the last to end at 10-under.
"I really wanted to get into a top-three finish. I thought that Henrik is obviously playing some phenomenal golf," Spieth said. "I really wanted to get out and play some smart golf today and limit the amount of bogeys. Once a few putts started falling, I thought I had a shot at it."
Stenson closed with three pars in a row to earn the win.
"I knew I had a par-5 coming up and if I could hit a good tee shot and get myself back in good position to make birdie, and once I made that one (on 15) ... I saw that Jordan was back down to 10-under, but Steve was a group ahead of me and he was 10-under at that moment," Stenson stated. "He would have had a chance, but I just fought hard for pars."
Stricker traded a bogey for a birdie from the first. He moved to 8-under with birdies at six, nine and 12. He buried a 23-foot eagle effort at 15 to jump to minus-10. Stricker could only par the last three to share second.
"I was thinking about winning the golf tournament. I was figuring if I could make birdie at 17, (Henrik) could bogey 17 and 18 just as easy as anybody else. Those are tough holes. I knew the putt (on 15) meant a lot, but I didn't know how much," said Stricker.
NOTES: Stenson picked up $1.44 million for winning the tournament, and earned a $10 million annuity for winning the FedExCup ... Stenson became the eighth player to win two FedExCup Playoff events in the same year ... Spieth was the youngest player to ever play in The Tour Championship and his share of second was the best-ever finish by a rookie at this event ... Brendon de Jonge, who was a captains pick for the International Presidents Cup team, ended 26th on the FedExCup points list and shared the tour lead with 30 tournaments played.