Sebastian Munoz remained in control of the Greenbrier Classic after shooting a three-under 67 to get to 12 under on Friday.
After a sterling nine-under 61 in round one, Munoz came back to earth a little, but still impressed with four birdies on his first seven holes.
He stumbled a bit on his back nine nine, bogeying holes three and six, but he birdied the par-four seventh hole to finish his round on a positive note.
Ben Martin and Hudson Swafford are tied for second at nine under.
Martin shot a three-under 67 Friday, while Swafford shot a bogey-free four-under 66.
Danny Lee, Russell Henley and 2016 United States Ryder Cup captain Davis Love III are all tied for fourth at eight under.
Jamie Lovemark headlined a group tied for seventh at seven under. The long hitter shot a bogey-free 64 in round two.
Phil Mickelson, playing his first event without long-time caddie Jim 'Bones' Mackay, shot a disappointing two-over 72 Friday to just make the cut on the mark at one under.
Charles Howell III, runner-up at the Quicken Loans National, also finished at one under.
Players Championship winner Kim Si-woo, Kevin Kisner and former world number one Luke Donald were among the notables to miss the cut.