David Lingmerth maintained his lead at the Quicken Loans National by carding a second successive five-under-par 65.
Searching for his second PGA Tour victory, Lingmerth made it around the TPC Potomac course bogey-free for a two-stroke lead after Friday's second round.
The Swede had five birdies, including the last at the 18th hole, to be clear of Geoff Ogilvy at 10 under overall.
Ogilvy - winner of the 2006 U.S. Open - catapulted himself into second position with a second-round 65.
The Australian only dropped one shot, a bogey at the 15th, to be within striking distance of the leader.
Daniel Summerhays heads into the weekend in third at six under. The American posted a two-under 68.
TPC Potomac at Avenel Farm has been giving players problems this week, which led to a four-over-par cut line.
World number nine Rickie Fowler shot a 72 on Friday, but snuck inside the cut line at two over.
That's just cruel. pic.twitter.com/A01hTTMjGM-- PGA TOUR (@PGATOUR) June 30, 2017
Justin Thomas, however, was not as lucky. The four-time PGA Tour winner recorded a 71 to miss the cut at five over. He has now missed two straight cuts since contending at the U.S. Open.
Reigning US PGA Championship winner Jimmy Walker also missed the cut after firing a five-over 75. A triple-bogey six on the par-three 17th ended his week early.