The two-time major champion holed out from 60 feet for birdie from a greenside bunker on the first hole of a playoff with Daniel Berger on Sunday at TPC River Highlands.
The 23-year-old Texan joined Tiger Woods as the only PGA Tour players with 10 victories in the era since World War II. Woods won 15 times before he turned 24.
“That was one for the ages,” said Spieth, also the winner at Pebble Beach in February.
Spieth held a one-stroke edge after each of the first three rounds. He closed with an even-par 70 to match Berger — who birdied three of the final six holes for a 67 — at 12-under 268.
Berger, the Memphis winner two weeks ago before missing the cut last week at the U.S. Open, just missed a 50-foot putt from off the 18th green left that would have forced a second playoff hole.
Jordan does Jordan things,” Berger said. “So there’s not really much you can say. I’m obviously disappointed, but happy to be in the position I was in today.”
Berger began the round in third place, three shots back. He tied Spieth for a lead with a 5-foot birdie putt on 15 as Spieth was making bogey on 14 and tied him again with a birdie from 8 feet at 17.
The pair, playing a group apart, both hit their approach shots on 18 into the same greenside bunker. Both chipped out close to the hole and both saved par to force the playoff.
