Tyrrell Hatton holds a one-stroke lead following the opening round of The CJ Cup at Shadow Creek, where the likes of Rory McIlroy, Brooks Koepka and Jordan Spieth ended the day over par.
The PGA Tour tournament is taking place in Las Vegas after being moved from South Korea because of travel restrictions imposed by the coronavirus pandemic, with world number one Dustin Johnson absent due to his positive COVID-19 test.
On the course, Englishman Hatton – who claimed last week's BMW PGA Championship via the European Tour – set the early pace with a seven-under-par 65 at Shadow Creek Golf Course on Thursday.
Looking to add to his sole PGA Tour victory after winning this year's Arnold Palmer Invitational, Hatton mixed an eagle with seven birdies and two bogeys.
It is Hatton's first career 18-hole lead on the PGA Tour as the 29-year-old tops the leaderboard ahead of Russell Henley and Xander Schauffele, having tied his career low nine-hole score by shooting a 30 on the back nine.
Spanish star Jon Rahm and Tyler Duncan are two strokes off the pace heading into the second round, a shot clear of Joel Dahmen, Ryan Palmer and Kevin Streelman.
Former world number one Jason Day posted a 70 to be two under – a stroke better off than Sergio Garcia.
Justin Thomas opened his title defence with a 72 after the two-time CJ Cup champion double bogeyed his final hole of the round.
Four-time major champion Rory McIlroy – playing for the first time since finishing tied for eighth at the U.S. Open – struggled on day one.
McIlroy bogeyed his final three holes as he signed for a one-over-par 73, while Koepka and Spieth did not fare much better ahead of next month's rescheduled Masters.
Returning following a two-month injury layoff due to hip and knee issues after missing the FedEx Cup playoffs and U.S. Open, Koepka had three birdies, a double bogey and three bogeys on a mixed day.
Out of form and without a title since capturing the 2017 Open Championship, Spieth experienced a similar round with four birdies, a triple bogey and three bogeys.