American golfer Webb Simpson set the pace on day one of the PGA Tour tournament in Georgia.
Justin Thomas moved top of the FedEx Cup standings after his win at the BMW Championship.
Troy Merritt leads the Northern Trust, but Dustin Johnson made a fine start in New Jersey.
South Korea's An carded a four-under-par 66 to preserve his position atop the leaderboard following Saturday's third round in Greensboro.
An Byeong-hun carded a five-under 65 to grab the outright lead at the Wyndham Championship.
World number one Brooks Koepka celebrated a three-stroke victory after carding a five-under-par 65 in Memphis on Sunday.
The honour of the opening tee shot at the 148th Open Championship went to Darren Clarke, who carded a 71 on Thursday.
Former world number one Rory McIlroy is among the leaders heading into the final round in Ontario.
Brandt Snedeker fired a 10-under 60 as Scott Brown and Matt Kuchar led the Canadian Open.
Dustin Johnson is in great position to win the RBC Heritage following three rounds of play.