ATLANTA — Xander Schauffele was six shots behind before he ever hit a shot Thursday in the new scoring format for the Tour Championship. His goal was to keep his head down, play good golf and see where he stood to par at the end of two days.

The TV cameras following his every move on the back nine at East Lake were the first hint it was going well.

A leaderboard on the 18th green confirmed it.

“I saw I was in first,” he said. “Happy with the day.”

Schauffele didn’t come seriously close to a bogey in a 6-under 64 that was the best score of the opening round by two shots. It was only worth a share of the lead with Justin Thomas and Brooks Koepka in a Tour Championship where players started with better scores to par than others depending on their place in the FedEx Cup.

Thomas, who started at 10-under par and a two-shot lead as the No. 1 seed, still led despite having trouble finding the fairway. That was the least of his problems on the back nine. He hit pitching wedge into the water for double bogey and missed a pair of 3-foot putts for a 70.

Instead of being six shots behind Schauffele, who started at 4 under as the No. 8 seed, Thomas was tied for the lead. Koepka, the No. 3 seed who started three shots behind, birdied three of his last four holes for a 67 to join them at 10 under.

“It’s weird on Thursday to be three back after a couple of holes,” Koepka said of the start. “It’s nice to close that gap on Day 1.”