Justin Thomas continued his breakout season by winning the Dell Technologies Championship at TPC Boston on Monday.
It was the fifth win of the season for Thomas, who was locked in a three-way battle with Jordan Spieth and Marc Leishman on the back nine before ultimately breaking away.
Thomas won by three shots at 17 under with a par on the par-five 18th hole.
The American got off to a hot start with two birdies and an eagle on his first seven holes, and he needed to after Spieth started his round five under through his first four holes.
But Spieth, who finished second at 14 under, shot two over on the back nine, leaving the door open for the US PGA Championship winner.
Thomas took advantage by remaining steady on the closing stretch to take another step towards claiming the FedEx Cup and the Player of the Year award.
Leishman finished third at 13 under after firing a one-under 70 on Monday, while it was a second straight runner-up finish for Spieth.
Jon Rahm (68) and Paul Casey (70) finished in a tie for fourth at 12 under. Casey has now finished in the top five in his last five play-off events.
Rahm, meanwhile, has never finished outside the top five in a play-off event in his young career.
Phil Mickelson led a group of four players tied for sixth at 11 under. It was Mickelson's first top 10 since June, but it may have been enough to earn a captain's pick from Steve Stricker for one of the final two Presidents Cup spots for the United States.
Despite the win, Thomas will still trail Spieth in the FedEx Cup standings heading into the BMW Championship in Chicago, beginning September 14.
Dustin Johnson dropped to third after finishing tied for 18th this week.