Bryson DeChambeau, playing his first PGA event since winning last month's US Open, fired a nine-under-par 62 to seize the early lead in Thursday's opening round of the Shriners Hospitals for Children Open.
World number six DeChambeau matched his PGA career-low round, including a career-best run of five consecutive birdies, in surging to the top of the leaderboard at par-71 TPC Summerlin in suburban Las Vegas.
"It was a great day to play well," DeChambeau said. "There's no wind out here for the most part and you feel like you can bomb it everywhere and hit wedges close.
"And I was lucky enough to make a lot of putts to start off my day."
The 27-year-old American's strategy of blasting the ball as far as possible with little worry about landing in the rough brought his first major victory at Winged Foot and a bogey-free round on Thursday.
Back-nine starter DeChambeau made seven birdies in eight holes starting with an 18-foot putt at the par-4 12th, followed by a six-footer for birdie at the par-5 13th and a tap-in par at the par-3 14th.
Then came his birdie run starting at 15, with the only final putt beyond five feet coming at the first when he dropped in one from just over 11 feet.
DeChambeau drove onto the green at the par-4 seventh and sank a two-foot birdie putt, then reached the fringe in two at the par-5 ninth and tapped in for birdie to seize the lead.
"I'm very pleased with how I played," DeChambeau said. "Didn't hit it my best but I put it in the right spots a lot of the time."
DeChambeau, who won the Shriners event in 2018 and shared fourth last year, fired his only prior PGA 62 in the second round of last year's 3M Open at Minneapolis.
This was the second year in a row at the Shriners that DeChambeau made a back-nine 30 in his opening round. His only other back-nine score so low came in the final round of his 2017 victory at the John Deere Classic.
In what he expects to be his only tuneup event for next month's Masters, DeChambeau found 11 of 14 fairways and 16 of 18 greens in regulation or better, driving the green on two par-4s with eagle putts on a trio of par-5 holes as well.
"I'm playing well and I feel like I have my golf swing under control and putting well, making a lot of putts. I feel like I can shoot low on a lot of golf courses and usually that wins tournaments."
Americans Austin Cook and Harold Varner shared second in the clubhouse on 63 with Argentina's Emiliano Grillo and Americans Brian Stuard, Andrew Landry and Rob Oppenheim next on 64 as the last groups teed off.