Jason Day of Australia posted a 67 to open up a three-shot lead at the half-way stage of the Wells Fargo Championship, with Rory McIlroy well down the field after his round of 73.
McIlroy is back on level par, some 10 shots behind the leader after a trying round, where he had five bogeys. He did managed to pick up shots on 10 and 14. Seamus Power, at two over, won't be around for the weekend after adding a 72 to his opening 70.
Day, who leapt ahead Thursday with a first-round 63, moved to 10-under (130) for his lowest 36-hole score in five years.
Max Homa shot a second-round 66 to take sole possession of second place at sevwn under. Luke List (66), Kurt Kitayama (67), James Hahn (68) and Denny McCarthy(69) were tied for third a shot further back.
Day, a former world No 1, continued a nice run of form Friday at TPC Potomacat Avenel Farm. After opening his round on the back nine and playing it to even par, he made three birdies and no bogeys on the front nine, including a 14-foot birdie putt at the par-3 third hole and an 11-footer at the par-4 eighth.
The Aussie is in search of his 13th win on tour and his first since the 2018 Wells Fargo. That victory came at the tournament's usual home of Quail Hollow in Charlotte.
TPC Potomac is filling in for 2022, with Quail Hollow set to host the Presidents Cup in the fall.