Russell Henley carded his first bogey of the tournament but still managed to double his lead at the Wyndham Championship on Friday.
Seeking his first PGA Tour win in four years, Henley shot 64 in the second round and sits at 14 under par for the tournament.
That left him four strokes up on Rory Sabbatini (64), Webb Simpson (65) and Scott Piercy (66) heading into the weekend in Greensboro, North Carolina.
Starting on the back nine at the Sedgefield Country Club, Henley bogeyed number 12, his third hole of the day, before reeling off four consecutive birdies from 14 through 17.
Three more birdies coming home after the turn solidified his edge as he eyes his first win since the 2017 Houston Open.
Henley's 126 matches the lowest 36-hole score posted on tour this season along with Stewart Cink at the RBC Heritage.
Tokyo Olympics silver medallist Sabbatini had a bogey-free day to match Henley's round, while Simpson remained near the top of the leaderboard thanks in part to an eagle at the fifth.
Simpson's success is no surprise, as he has finished in the top three at the Wyndham the last four years after winning it in 2011.
Tyler Duncan had the best round of the day with a 62 that left him five shots back at nine under along with Justin Rose (65) and Brian Stuard (66).
Among other notables, Bubba Watson (69) and Adam Scott are 10 strokes back at four under, one shot better than the cut line.
Masters champion Hideki Matsuyama (69) missed the cut by a stroke, while former world number one Luke Donald (67) finished at one under and two-time major winner Zach Johnson fell short at even par along with defending tournament champion Jim Herman.
Also finished for the week-end are Padraig Harrington (76) at two over, Rickie Fowler (72) at three over and Charl Schwartzel (73) at seven over.
Fowler's missed cut means his season is over, as he will not make the FedEx Cup playoffs for the first time in his career.
Two players who were tied for second after Thursday's opening round, Michael Thompson and Ted Potter Jr., also missed the cut after slumping to 74 and 77, respectively.