PGA Tour news: Davis Thompson leads American Express, Jon Rahm tied for second

Thompson, playing in only his ninth PGA Tour event, eagles two-par fives on the way to his 10-under total at La Quinta Country Club in California, one of three courses being used for this week's event.

"(I) just got off to a hot start and just kind of coasted on my way in," he said. "But it's always good to see some putts go in early and give you confidence to just keep it rolling."

"My biggest challenge today was staying present-minded and trying to put one foot in front of the other. Your mind definitely starts to wander a little bit. But I played enough rounds to where I try to teach myself over and over you can't get ahead of yourself."

Five players lie two shots behind in a tie for second - Taylor Montgomery and Spain's Jon Rahm each shot 8-under 64 at La Quinta, while Sam Burns and Germany's Matti Schmid both carded a 64 at PGA West's Stadium Course, and Tyler Duncan had a 64 at PGA West's Nicklaus Tournament Course.

Rahm made five birdies on his first seven holes at La Quinta and then followed up a lone bogey with four more gains coming home.

"It's a great start to the tournament," said Rahm, who won this event in 2018. "You can't really win it on this golf course, but you can sure fall off the pace. It's a great start, solid round of golf, great putting out there. Hopefully, I can keep that going the whole week and feel a little bit better tee to green."

As many as nine players lie a further shot back, three off the lead, including South African duo Erik van Rooyen and Dean Burmester, Xander Schauffele and Sungjae Im.