Zac Blair and Grayson Murray, both starting on the back nine but playing on different courses, hold the first-round lead at The American Express in La Quinta, Calif., after shooting 8-under par 64s on Thursday.
A trio of golfers -- Hank Lebioda, Scottie Scheffler and Rickie Fowler -- are a shot back.
The pro-am with a 54-hole cut line is played over three courses: La Quinta Country Club, the Stadium Course at PGA West and the Nicklaus Tournament Course at PGA West.
Playing at La Quinta, Blair birdied Nos. 11 & 13 -- the first par 5s he played Thursday -- then birdied the par-4 No. 17 to make the turn at 3 under. The 224th-ranked player in the world then caught fire from there, with birdies on Nos. 1, 2, 5, 6 and 8. The fifth and sixth holes are the other par 5s on the course, making him 4-under par on par 5s Thursday.
Murray, the No. 463 player in the Official World Golf Rankings, played at the Stadium Course and shot a blistering 30 on his first nine holes, hitting the turn with four straight birdies. He birdied three of the next eight holes to get to 9 under, but he bogeyed the par-4 ninth hole.
Behind the three golfers tied for third is a group of eight. Among that group are Russell Knox, Andrew Landry and Cameron Davis. Defending champion Adam Long shot a 3 under on the La Quinta course and is tied for 49th.
Between the two of them, Blair and Murray have one career win on the PGA Tour -- Murray at the Barbasol Championship in 2017.
On the amateur side, WNBA commissioner Cathy Engelbert is 12-under par, one stroke better than a quartet of golfers.