South Korean duo Byeong Hun An and Sungjae Im are co-leaders following the opening round at the Wyndham Championship in North Carolina.
Both shot the best rounds of their PGA Tour careers, sinking eight birdies to card eight-under-par rounds of 62 at Sedgefield Country Club and put themselves one shot ahead of the chasing pack.
"I've got to do a couple more of these rounds," 27-year-old An said.
"One good round won't do it, so I need to keep it up and make a lot of birdies."
Canadian Mackenzie Hughes, South Africa-born Slovakian Rory Sabbatini and Americans Patrick Rodgers and Johnson Wagner sit joint third on seven under, while former World No.1 Jordan Spieth is part of a nine-way tie for seventh.
"I've got to do a couple more of these rounds … One good round won't do it, so I need to keep it up and make a lot of birdies." – Byeong Hun An
The Texan had just 23 putts during his round.
"You want putts for birdie. You want to be hitting greens in regulation," Spieth said.
"Really, two bad swings today kept it from being my lowest round on the PGA Tour. There's a lot of good in that."
Cameron Smith and Cameron Davis shot four-under (66) to lead the Australian contenders which included Matt Jones (69), Rod Pampling (70), Curtis Luck (70) and John Lyras (73).
The event in Greensboro is the final one of the regular season, with players aiming to secure places in the top 125 of the FedEx Cup standings and be eligible for the play-offs.