Kitayama missed the cut in his last five starts but that didn't stop him from posting a six-under score at the PGA National Resort and Spa's Champion Course, known to be a challenging layout.

He leads Daniel Berger, Chris Kirk and Rory Sabbatini, who all signed for 65.

Kitayama started on the back nine and birdied his first three holes, then recovered from a lone bogey by stringing together four more birdies at holes 3-6, the last a 21-foot putt from just off the green.

"Getting off to a start like that helps you relax," Kitayama said. "It takes a little pressure off going into the Bear Trap (Nos. 15-17 at PGA National). For me, starting off that way kind of calms me down."

"When you're struggling, I think (there's) just that self-motivation to keep getting better and finding a way to figure it out." - Kurt Kitayama.

The 29-year-old has three worldwide wins in Europe and Asia but none on the PGA Tour.

"When you're struggling, I think (there's) just that self-motivation to keep getting better and finding a way to figure it out," he said. "It's kind of how you've got to keep going."

Berger compiled five birdies, four on the front nine, during a bogey-free round. The Florida native is one of the highest-ranked players (No.21) in the Honda field.

"I felt really comfortable out here and I got some good prep leading up to the week," Berger said.

"I came out on Sunday before the tournament and played some golf. It was kind of a mellow week in terms of preparation, and like I said, sleeping in your own bed is always amazing."

Kirk had a wild ride with eight birdies and three bogeys, while the 45-year-old Sabbatini matched Berger by avoiding bogey at PGA National for the first time in his career.

"When I did miss it today, I actually missed it in the right spots," said Sabbatini, who carded five birdies.

Tied for fifth at three-under are Peter Uihlein, Andrew Kozan, Englishmen Aaron Rai and Danny Willett and Austria's Matthias Schwab.

Chile's Joaquin Niemann, last week's champion at the Genesis Invitational, opened with an even-par 70 and is tied for 45th.

South African star Louis Oosthuizen carded six bogeys and one double bogey en route to a five-over 75.

Defending champion Matt Jones, who shot an opening-round 61 last year, recorded a 73 to leave him one shot behind the leading Australian, Lucas Herbert.