JJ Henry stormed into the lead of the Shriners Hospitals for Children Open in Las Vegas after shooting a course record of 60 in the opening round.
Starting on the back nine, Henry began with just one birdie in his opening five holes, but he approached the turn on four under before a blistering performance on the front nine at TPC Summerlin.
The American birdied the second, fourth, five, sixth and eighth holes before sinking a long eagle putt from just off the green on the ninth to reach 11-under par for the day.
"It was one of those days. There wasn't much wind and the greens were pretty soft. It was nice to make that putt on the last hole," Henry told the PGA Tour's official website.
"I played solid on the front nine. It's still pretty cold in the morning (Henry started at 7.42am). I was just trying to get my feet wet and shoot a couple under par."
Henry has never finished better than 46th at the tournament and will likely need to continue to pick up shots over the weekend the past three winners of the event have all shot at least 20-under par.
The 38-year-old, a two-time PGA Tour winner, opened the 2013-14 season at the Frys.com open last week with a 16th-placed finish.
He added: "Any time you start with the round I had, it gives you a lot of confidence for the rest of the week."
Despite his heroics, Henry was just a single stroke ahead of Andres Romero, who had two eagles in another flawless round on a low-scoring day in Nevada.
The Argentinian had an opportunity to match Henry's score but missed his 29-foot birdie putt on the final hole. However, it was still Romero's career-low score by three shots.
He said: "I was feeling very good this week, my swing was there, I was hitting the ball well and I had a really good round. I thought I was going to finish leader but unfortunately Henry had one more birdie."
American trio James Driscoll, Jonathan Byrd and Jeff Overton were all on eight under to be tied for third while 2012 US Open champion Webb Simpson was a shot further back.
Canada's Stephen Ames, John Senden of Australia and American quartet Bryce Molder, Scott Brown, Heath Slocum and Chesson Hadley finished on six under.
World No 11 Zach Johnson, who is a clear favourite this week, is nine shots off the lead.