On a bogey-free first round, Schauffele finished with a 6-under 64, which puts him at 10-under for the tournament after he started at 4-under par.

The American shares the lead with world number one Brooks Koepka and FedEx Cup leader Justin Thomas, who finished 3-under and level par for the day, respectively.

Under the new format, Thomas started the event at 10-under par by virtue of being top of the FedEx Cup standings going into the season finale.

Second seed Patrick Cantlay started at 8-under, with subsequent descending scores down to even par for players ranked between 26th to 30th.

Schauffele, however, quickly made up the disadvantage, although he admitted he remained confused by the scoring system.

“You know, I have no idea how this whole thing works,” he was quoted as saying by ESPN. “You know, we have a number. We have a seeding. I mean, that’s how I’m taking it. I think everyone needed help from J.T. [Justin Thomas].

“If J.T. [Justin Thomas] went out and shot a pair of 65s, I don’t think the Tour would be very happy, and I don’t think the rest of the field would be happy.”

Thomas began the tournament with a two-shot lead over his closest competitor, Patrick Cantlay, but endured a difficult first round with two bogeys and one double-bogey.

Luckily for him, the buffer he held over the rest of the field was significant enough to allow him to remain ahead of his rivals, albeit as joint-leader.

Rory McIlroy sits behind the trio at 9-under, with Matt Kuchar and Patrick Cantlay at 8-under and Hideki Matsuyama a shot further behind.

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

Tee Times (All times ET)

12 p. m. —Lucas Glover, Brandt Snedeker12:10 p. m. —Webb Simpson, Jason Kokrak12:20 p. m. —Marc Leishman, Dustin Johnson12:30 p. m. —Louis Oosthuizen, Chez Reavie12:40 p. m. —Rickie Fowler, Kevin Kisner12:50 p. m. —Tommy Fleetwood, Abraham Ancer1 p. m. —Charles Howell III, Bryson DeChambeau1:10 p. m. —Corey Conners, Tony Finau1:20 p. m. —Sungjae Im, Justin Rose1:30 p. m. —Adam Scott, Gary Woodland1:40 p. m. —Jon Rahm, Patrick Reed1:50 p. m. —Hideki Matsuyama, Paul Casey2 p. m. —Matt Kuchar, Patrick Cantlay2:10 p. m. —Justin Thomas, Rory McIlroy2:20 p. m. —Xander Schauffele, Brooks Koepka

TV and live stream guide

On Friday, coverage begins at 1 p.m. ET on Golf Channel and runs until 6 p.m. ET. Coverage of featured groups will be available between 11:30 a.m. ET via PGA Tour Live.

Golf Channel will also broadcast live action between 1 p.m. ET and 2:30 p.m. ET on Saturday and between 12 p.m. ET and 1:30 p.m. ET on Sunday.

NBC will take over at 3 p.m. ET on Saturday and at 2 p.m. ET on Sunday, covering the final two rounds.

All four days of the tournament can be watched online via PGA Tour Live and on Golf Channel’s digital platforms, while the last two rounds will also be available online via NBC’s website.

A live stream for all the four rounds will be available via fuboTV.

The Tour Championship Leaderboard

-10—Xander Schauffele, Brooks Koepka, Justin Thomas-9—Rory McIlroy-8—Matt Kuchar, Patrick Cantlay-7—Hideki Matsuyama-6—Jon Rahm, Paul Casey, Patrick Reed-5—Adam Scott, Gary Woodland

The complete leaderboard is available on the PGA Tour’s official website.