Rookie Mackenzie Hughes retained control of the RSM Classic, taking a two-shot lead at the halfway mark on Friday.
The Canadian carded a five-under 67 on the Plantation course to move to 14 under at Sea Island, Georgia.
Pan Cheng-tsung is outright second after producing a six-under 64 on the Seaside course.
But it is Hughes, the 25-year-old with two professional wins to his name, who has command after he went through bogey-free during his second round.
There is a logjam on the leaderboard behind Hughes and Pan.
Hudson Swafford (67), Blayne Barber (68), Chad Campbell (65) and Chesson Hadley (66) are tied for third at 11 under.
A shot behind them are a group of 10 players, among them Billy Horschel (66) and Charles Howell III (65).
Defending champion Kevin Kisner (72) missed the cut, as did Ernie Els (74) and Vijay Singh (72).