Si Woo Kim followed his tournament-record 10-under 60 with a 64 on Saturday to increase his lead to three strokes in the Wyndham Championship.
The 21-year-old South Korean player had an 18-under 192 total at Sedgefield, a stroke off the tournament 54-hole record set by Carl Pettersson in his 2008 victory.
Kim is in contention for his first PGA Tour victory for the second time in a month after losing a playoff to Aaron Baddeley in Alabama in the Barbasol Championship.
Kim played the front nine in 3-under 35 with four birdies and a bogey, added birdies on the par-4 13th and par-5 15th and parred the final three holes.
Rafa Cabrera Bello was second after a 65 in the PGA Tour's regular-season finale. The Spaniard was fifth last week in the Rio Olympics.
Jim Furyk, Luke Donald and Kevin Na were 13 under.