Los Angeles - Grayson Murray fired a five-under-par 67 to claim a one-shot lead after the first round of the Valero Texas Open in San Antonio on Thursday.
The 24-year-old from North Carolina, chasing only his second career win on the PGA Tour, edged clear of the field thanks to some long putting and solid iron play on the par-72 TPC San Antonio Oaks course.
The American got off to a dream start, opening with back-to-back birdies on his first two holes before a superb chip from the fairway gave him a birdie tap-in on the fifth to move to three under.
His round threatened to come apart on the par-three seventh, when he needed three shots to get onto the green before two-putting for a double-bogey five.
However, Murray came storming back on the back nine, draining a 28-foot putt on the 11th for a birdie and then sinking another long putt on the 13th to move back to three under.
Two more birdies on the 17th and 18th saw him finish at five under, setting him up to challenge for his second title following a breakthrough win at the 2017 Barbasol Championship in his rookie season.
Five players were tied for second, a shot off the lead on four under, including Chesson Hadley, Billy Horschel, Ryan Moore, Keegan Bradley and Matt Atkins.
Five players - Andrew Landry, Jon Curran, Harris English, Joshua Creel and Mexico's Roberto Diaz - were tied for seventh on three under, two off the lead.
A cluster of nine players, including Zach Johnson and Brandt Snedeker, were on two under after carding 70s.
Leading scores after Thursday's opening round of the PGA Tour's Texas Open at San Antonio, Texas (USA unless noted, par 72):
67 - Grayson Murray
68 - Chesson Hadley, Billy Horschel, Ryan Moore, Keegan Bradley, Matt Atkins
69 - Andrew Landry, Jon Curran, Roberto Diaz (MEX), Harris English, Joshua Creel
70 - Brendan Steele, Brandt Snedeker, Nick Watney, Abraham Ancer (MEX), Keith Mitchell, Zach Johnson, Austin Cook, David Hearn, Corey Conners