DA Points leads the Houston Open after the first round with Rory McIlroy in danger of missing the cut.
Brian Davis, Lee Westwood and Greg Owen lead the British challenge but McIlroy is nine shots behind American leaders Points.
Points made the most of a superb start to fire an eight-under-par 64 to lead by one from compatriots Cameron Tringale and John Rollins.
Davis is three shots off the lead, with Westwood and Owen a further shot behind.
But there was no upturn in fortunes for McIlroy, whose poor form this year has seen him lose the world No 1 spot to Tiger Woods.
He was one-over for a share of 88th and in danger of failing to make the cut.
Points began his tournament with five straight birdies after starting his round at the 10th, and added another before the turn.
Three more followed on a front nine marred only by a bogey at the fifth as he finished one shot ahead of Tringale and Rollins, who each carded seven birdies in unblemished rounds.
Afterwards, Points revealed he had been using his mum's old putter - which he used when he first turned pro - in an attempt to turn around some bad form on the green.
He told pgatour.com: "It's just a really good-looking putter, and I brought it with me this week because I just had been putting so bad, I thought maybe I'll pull this old putter out of the garage and maybe it will have some magic in it. Sure enough, today it did."
Jason Kokrak and Argentina's double major winner Angel Cabrera shared fourth on six under with Davis, former Ryder Cup player Jeff Overton and Steve Wheatcroft a shot further back.
Westwood and Owen were among a large group sharing ninth place on four-under.
Westwood found the water twice at the eighth - one of three bogeys in his round - and said: "I must have the worst par fives of anyone this year.
"It was like dropping four shots really. A 68 is as high as I could have shot."