HILTON HEAD ISLAND, S.C. -- Matt Fitzpatrick's earliest memories of Harbour Town were as a spectator wondering if Tiger Woods would play the RBC Heritage.

He was always disappointed, since Woods played only once at Hilton Head, in 1999, when Fitzpatrick was 4 years old.

"I remember saying to my dad, 'Is Tiger going to be here?'" he recalled.

Now, Fitzpatrick's got a sweeter memory at the Pete Dye layout he played as a child on vacations.

Fitzpatrick defeated defending champion Jordan Spieth on the third playoff hole on Sunday, stuffing his approach in close on the par-4 18th to secure his first victory since the U.S. Open last June.

"I think I can retire now," joked the 28-year-old Englishman, who uses a Harbour Town-style lighthouse headcover. "This is one I really wanted."

Fitzpatrick hit 9-iron to within one foot on the closing lighthouse hole to set up the winning birdie.

Fitzpatrick had to sweat out a couple of prime chances by Spieth on the first two extra holes. Spieth raised his putter in triumph before watching his 12-foot birdie putt catch the right edge and spin out the first time the pair played the 18th. Then Spieth's 9-foot birdie attempt ran out of steam on the right edge at the 17th hole.

"I felt every putt he hit was going to go in," Fitzpatrick said.

Spieth still doesn't understand how that first playoff putt didn't drop.

"I think if I hit the same putt 10 times, it does in eight," Spieth said. "It should go left at the very end there on the grain. It just wasn't meant to be."

There was no doubt about the final hole as Fitzpatrick, from 187 yards out, hit the front of the green and watched his ball settle next to the hole. Spieth's attempt from 26 feet away rolled past and Fitzpatrick tapped in for the victory.

Fitzpatrick felt the shot was true from the moment he struck it. He wasn't sure how close it came but got an idea when he spotted his family cheering wildly.

"I knew it was good because my mom and my girlfriend were jumping up and down," he said.

Fitzpatrick won $3.6 million from the elevated purse of $20 million in the sixth designated event of the year on the PGA Tour, topping a field that included seven of the world's top 10 players.

Fitzpatrick trailed Spieth by 2 strokes with five holes to play but made birdies on the 15th and 16th holes to tie for the lead at 17 under.

The third-round leader by 1 shot, Fitzpatrick closed with a 3-under 68 and matched Spieth at 17-under 267. Spieth had his second straight 66.

Patrick Cantlay, grouped with Fitzpatrick and Spieth, was third after a 68 left him at 16 under. Cantlay lost this title in a playoff to Spieth a year ago.

"Another close call here," Cantlay said.

Xander Schauffele was another stroke behind after a 66. Sahith Theegala shot 65 and Hayden Buckley a 67 to tie for fifth at 14 under.

Scottie Scheffler, No. 2 in the world, shot 70 and was tied for 11th at 12 under. Masters champion Jon Rahm ended with a 68 and was tied for 15th before taking a well-earned week off.

Fitzpatrick carried a 1-shot lead into the final round but watched as Spieth made four birdies in the opening six holes to share the lead.

Fitzpatrick played a stretch of nine holes in 1 over as Spieth looked ready to pull away. But Spieth made bogey on the par-3 14th while Fitzpatrick answered with consecutive birdies on the 15th and 16th.

The pair remained tied until Fitzpatrick's remarkable approach on the winning hole.

Cantlay, so close a year ago, lost his chance at victory with consecutive bogeys on the 13th and 14th holes. He missed from inside 2 feet for the first, then saw his chip off the green on the next hole end up wedged next to a wood pylon at the edge of the water.

Cantlay was able to pop it up and complete the most improbable bogey he's had in a while.

Masters champion Rahm set his sights on donning the plaid jacket given winners here to go with the green one he brought from Augusta National. But a 1-over 72 Thursday set him back and he never challenged the lead despite shooting in the 60s the final three rounds.

Rahm played his final 33 holes in 2 under and closed with birdie on the last, his approach settling inside 2 feet.

The crowd cheered and chanted as he applauded them back with a big smile. Rahm will return in two weeks to defend his Mexico Championship title.

"To be honest, I didn't expect this," Rahm said of the fans. "I did not expect this in my wildest dreams. To see the kids, the adults and everybody have that reaction just to see me is really very special."