Francesco Molinari grabbed a one-shot lead at the Wells Fargo Championship after an opening-round six-under 66 as Dustin Johnson made a solid return.
Molinari holed eight birdies and two bogeys at the Quail Hollow Club on Thursday to edge clear atop the leaderboard.
But all eyes were on Johnson, the world number one making a return from a back injury suffered before this year's Masters.
The American, already a three-time winner in 2017, carded a two-under 70 to be tied for 15th after mixing four birdies with two bogeys.
Dustin Johnson shoots a 2-under 70 in his return to competitive golf.-- PGA TOUR (@PGATOUR) May 4, 2017
He hasn't shot over par since January. pic.twitter.com/gdouOqJTj7
A group of four players are behind Molinari in a tie for second, including American Grayson Murray.
Murray had appeared set to hold the overnight lead before bogeys on his final two holes saw him slip back to five under.
Countrymen Brian Campbell and J.B. Holmes, the 2014 champion, and Swede Alex Noren also opened with 67s.
A relatively congested top part of the leaderboard sees Ben Martin, Ken Duke and Seamus Power at four under, a shot ahead of Shawn Stefani, Noh Seung-yul, Chris Kirk, Jon Rahm, Rafa Cabrera Bello and Jonathan Randolph.
Rahm, the talented Spaniard, claimed his first PGA Tour win at the Farmers Insurance Open in January, but a bogey-birdie-bogey-birdie patch on the back nine cost him an even better round.
Defending champion James Hahn produced an even-par 72 to be tied for 53rd after the first round.