Xander Schauffele had a 6-under 64 for the best opening round at East Lake by two shots. It was only worth a share of the lead Thursday in a Tour Championship where 30 players were given a head start based on their position in the FedEx Cup.

Justin Thomas, who started at 10-under par and a two-shot lead as the No. 1 seed in the FedEx Cup, hit pitching wedge into the water for double bogey and twice missed 3-foot putts in his round of 70. Instead of being six shots behind, he goes into the second round tied.

Brooks Koepka birdied three of his last four holes for a 67 and joined them at 10-under par.

Justin Thomas hits from the third fairway during the first round of the Tour Championship golf tournament Thursday, Aug. 22, 2019, in Atlanta. (AP PhotoJohn Amis)

Justin Thomas hits from the third fairway during the first round of the Tour Championship golf tournament Thursday, Aug. 22, 2019, in Atlanta. (AP PhotoJohn Amis)

The score to par is all that matters in deciding who wins the FedEx Cup and the $15 million prize.

Brooks Koepka tees off to the second hole during the first round of the Tour Championship golf tournament Thursday, Aug. 22, 2019, in Atlanta. (AP PhotoJohn Amis)

Brooks Koepka tees off to the second hole during the first round of the Tour Championship golf tournament Thursday, Aug. 22, 2019, in Atlanta. (AP PhotoJohn Amis)

Rory McIlroy, of Northern Ireland, watches his tee shot to the second hole during the first round of the Tour Championship golf tournament Thursday, Aug. 22, 2019, in Atlanta. (AP PhotoJohn Amis)

Rory McIlroy, of Northern Ireland, watches his tee shot to the second hole during the first round of the Tour Championship golf tournament Thursday, Aug. 22, 2019, in Atlanta. (AP PhotoJohn Amis)