Patrick Rodgers carded a second round 64 to establish a two-shot halfway lead at the John Deere Classic.
The 25-year-old American had eight birdies and a single bogey in his seven under par round, which left him 13 under for the week in Illinois.
That was two clear of Bryson DeChambeau, who signed for a 65, with two-time major winner Zach Johnson and overnight joint-leader Charles Howell III a shot further back in a tie for third at TPC Deere Run.
Rodgers, a former world amateur number one, matched Tiger Woods' Stamford University record of 11 wins during his college career but is yet to make his mark since turning professional in 2014.
Starting on the back nine, Rodgers carded birdies at the 14th and 16th from 17 and 13 feet before tapping in for another gain on the 17th.
A chip-in at the second and a 50-foot effort on the seventh were the highlights of five inward birdies, but Rodgers three-putted the ninth - his last - to drop his only shot of the day.
Birdies at 17 and 18 helped Seamus Power squeeze inside the cut line to continue his weekend. He is two-under in a tie for 70th position.
