Justin Rose carded a six-under 65 to take the lead after the first round of the Dell Technologies Championship.
The Englishman handled windy conditions to hit a bogey-free round at Boston TPC - one of only two players to do so.
His lead is small, however, with Abraham Ancer and Scotland's Russell Knox hot on his heels just one shot behind on five-under.
Knox got off to a flying start with a birdie on the par-4 opening hole, before cancelling out two bogeys with an eagle on the par-4 15th and finishing with a 15-foot birdie putt.
Ancer, who started on the back nine, completed his round with four birdies over the final six holes.
Rory McIlroy was looking at a one over for his day on Friday until a birdie on 18 brought him back to even.
Four Americans - Chris Kirk, Beau Hossler, Keegan Bradley and Gary Woodland - make up a group tied for fourth on four-under, while Dustin Johnson and Rafa Cabrera Bello are among eight sitting on 68.
Tiger Woods struggled to keep up the form he showed at this month's USPGA, finishing round one on 72.
Woods currently sits 25th in the FedEx Cup standings, with the top 70 making it to next week's BMW Championship and the top 30 ultimately qualifying for the season-ending Tour Championship.