Starting from tee No. 10, the world No. 1 set out his stall early, making a 15-feet eagle on the 11th hole—his second of the tournament—after he ripped a 4-iron some 275 yards.

McIlroy added birdies at the 15th and second holes, before bogeying the fourth. The Northern Irishman quickly recovered and birdied three of the last four holes to finish the first round two shots ahead of Bubba Watson and Justin Thomas.

The 30-year-old returned to the top of the world rankings for the first time in four years two weeks ago, but suggested his new-found confidence stemmed from his game rather than his ranking.

“I’m confident because I am playing well,” he said. “Regardless whether I have a 1 or a 2 or a 10 beside my name in the world rankings, I’m comfortable with my game, I’m comfortable with what I’m doing and that’s the most important thing.”

Behind McIlroy, Watson and Thomas finished on 67. The former of the American pair missed the cut at the Genesis Invitational at Riviera Country Club last week, but was pleased his attacking approach had paid off.

“Freed it [his game] up and just had some fun and realized I was in a good frame of mind,” he told reporters after his round. “Who cares about missing a cut, really? We’ve got other things to worry about.”

Local hero Abraham Ancer finished with a 1-under-par 70 and needed three straight birdies to overcome a difficult start, while world No. 3 Jon Rahm finished with 72 despite not making a birdie until the 15th hole.

Defending champion Dustin Johnson endured a difficult day at the office, carding a 5-over-par 76—his highest opening round since the British Open at Carnoustie in 2018.

The American has won twice at Chapultepec in three years and entered the tournament as the bookmakers’ second favorite but was uncharacteristically off color on Thursday.

Meanwhile, a week on from winning the Genesis Invitational, Adam Scott shot a 3-over-par 74, with Jordan Spieth posting the same score.

Here’s everything you need to know ahead of Friday.

Round 1 leaderboard

Rory McIlroy -6Bubba Watson, Justin Thomas -4Louis Oosthuizen, Billy Horschel, Bryson DeChambeau, Corey Conners -3Tyrrell Hatton, Paul Casey, Patrick Reed, Lee Westwood, Hideki Matsuyama, Sungjae Im -2

Selected tee times (all times ET)

Tee No. 1

12:03 p. m. —Collin Morikawa, Benjamin Hebert, Zach Murray1:03 p. m. —Jason Kokrak, Zander Lombard, Shugo Imahira1:39 p. m. —Kevin Kisner, Xander Schauffele, Paul Casey1:51 p. m. —Francesco Molinari, Dustin Johnson, Abraham Ancer2:03 p. m. —Tommy Fleetwood, Gary Woodland, Rory McIlroy2:15 p. m. —Patrick Reed, Christiaan Bezuidenhout, Sungjae Im

Tee No. 10

12:03 p. m. —Lucas Herbert, Tae Hee Lee, Kurt Kitayama12: 15 p. m. —Bernd Wiesberger, Bryson DeChambeau, Matthew Fitzpatrick12:39 p. m. —Hideki Matsuyama, Marc Leishman, Justin Thomas12:51 p. m. —Adam Scott, Carlos Ortiz, Jon Rahm1:03 p. m. —Shane Lowry, Jordan Spieth, Sung Kang1:15 p. m. —Tyrrell Hatton, Scott Hend, Byeong Hun An1:27 p. m. —Bubba Watson, Louis Oosthuizen, Ryo Ishikawa

TV coverage

Coverage on Friday begins at 2 p.m. ET on Golf Channel and runs until 6:30 p.m., with a live stream available on PGA Tour Live, Golf Channel’s digital platforms and fuboTV.