Washington (AFP) - Scott Stallings defied tough playing conditions to fire 10 birdies and an eagle in an 11-under 60 on Saturday at the PGA Barbasol Championship.
Stallings' 19-under total of 194 put him one stroke in front of fellow American Grayson Murray, who had four birdies on each side with one bogey in a seven-under 64 on the Robert Trent Jones Golf Trail Grand National layout in Auburn, Alabama.
Stallings opened with back-to-back birdies and after picking up another stroke at the fourth, he eagled the par-five fifth.
A bogey at six was followed by birdies at eight and nine, and he made five birdies coming in - including three to cap his round.
When his 12-foot putt at the 18th dropped, it marked the second 60 in as many days on the rain-softened course, after Chad Collins on Friday.
Stallings hit every green in regulation and his only bogey came by way of a three-putt.
But Stallings said he hadn't spared much thought for his score, concentrating instead on coping with the draining heat.
"It's brutal hot out there," said Stallings, who won the last of his three PGA Tour titles in 2014.
"That was a good distraction for me," he added.
"It's easy to lose your train of thought. I ran into that yesterday. I was playing great and let my mind go a little bit and faltered a little bit coming in.
"My goal out there today was to put myself in the same position and finish it off better than the day before."
Overnight leader Collins followed his 60 with a 69 that left him in a tie for third on 196 with Tag Ridings, who carded a 63.
The tournament, played opposite the British Open at Royal Birkdale, features a field largely drawn from outside the top 125 on the PGA season points list looking to rise and qualify for the season-ending play-offs.