Bryson DeChambeau opened up a two-stroke lead at the Safeway Open after firing an 8-under 64 in the second round, while Tony Romo missed the cut.
American DeChambeau produced a bogey-free round in Napa, California, to move into 12 under on Friday.
DeChambeau made three birdies on the front nine before five more followed, including three straight from 10 through 12.
A five-time winner on the PGA Tour, DeChambeau holds a two-shot lead over Nick Watney (65).
Justin Thomas carded an 8-under 64 to be among five players tied for third at 9 under.
Nick Taylor (66), Dylan Frittelli (65), Adam Long (68) and Cameron Champ (68) are alongside Thomas.
Defending champion Kevin Tway was among those who missed the cut after shooting rounds of 71 and 72.
Romo, the Dallas Cowboys great and an amateur golfer, fired a second-round 78 to finish at 4 over.