Brandon Hagy fired an 8-under 64 at the Nicklaus Tournament Course to claim the first-round lead at The American Express.
The long-hitting 29-year-old overcame two bogeys with a whopping 10 birdies, including three separate streaks of three straight circles on his scorecard.
"I hit a lot of iron shots close, and I made kind of those 10- to 15-foot mid-range putts the whole day, which you're going to have to make a few of those to put 10 birdies on the card," Hagy said afterward.
This marks Hagy's second lead or co-lead after Round 1 of his career. He led in the 2017 Canadian Open and went on to finish tied for fifth.
Sitting one back of Hagy is South Korea's Byeong Hun An, who also posted his low round on the Nicklaus Tournament Course.
Si Woo Kim shot 66 for the lowest score on the Stadium Course, which will host the tournament's weekend rounds from La Quinta, California.
Here's how the top of the leaderboard stands after Day 1:
|Place||Player||To Par||R1 Score|
|1||Brandon Hagy (NT)||-8||64|
|2||Byeong Hun An (NT)||-7||65|
|T3||Si Woo Kim (SC)||-6||66|
|T3||Martin Laird (NT)||-6||66|
|T3||Max Homa (NT)||-6||66|
The Nicklaus Tournament Course played a half stroke easier than the Stadium Course in Round 1. The field will swap courses for Round 2, which begins at 12:10 a.m. ET. The broadcast starts at 3 p.m. on Golf Channel.