Marc Leishman has fired the best round of his PGA Tour career to storm into the clubhouse lead at the AT&T Byron Nelson.
Leishman shot a 10-under par 61 to hold a three-stroke advantage late in the opening round at Trinity Forest in Dallas.
The 34-year-old Victorian, a three-time winner on the PGA Tour, started with an eagle on the par-5 first hole and never looked back, claiming another eagle at the 14th to go with six birdies.
Leishman, who left himself a four-foot putt on the 18th for his 61, said the thought of shooting 59 barely crossed his mind.
"I didn't think about that," he said. "I didn't want to let myself get ahead of myself which was good.
"Sixty-one. I'll take that."
Leishman had previously posted four scores of 62, including his opening round in last year's BMW Championship which he went on to won by five shots.
Perhaps the most pleasing thing for the Aussie was that it was a blemish-free opening round, with ten pars to go with his eight scoring holes.
The world No.16 didn't miss a fairway for just the third time during his career.
"That's the key around here," he said. "The fairways are generous but if you are off them you are in trouble."
Americans Jimmy Walker and J.J. Spaun are the next best challengers in a tie for second at 7-under, with a group of players a stroke further back in a tie for fourth.
Keegan Bradley holds the course record of 60 at the Byron Nelson Championship but curiously, the Americans 2013 feat gave him a round of minus-10, just like Leishman.
Fellow Australian Adam Scott fired a four-under par 67 while Cameron Percy got his round to five-under par through 15 holes.