Russell Henley surged to the top of the leaderboard at the Tour Championship in Atlanta with a superb nine-under-par 61, giving the American a two-stroke lead after the opening round.
The 36-year-old, who has already sealed his place in the United States Ryder Cup team, holed an impressive 207 feet of putts and produced a flawless round featuring seven birdies and an eagle.
However, world number one Scottie Scheffler is lurking ominously in second place after a bogey-free 63. The defending FedEx Cup champion finished strongly with birdies on the 15th, 17th and 18th holes, while a scrambling par on the 16th also proved crucial in keeping him within striking distance.
Scotland’s Robert MacIntyre, whose final-round stumble handed Scheffler victory at the BMW Championship on Sunday, sits at six under alongside England’s Tommy Fleetwood.
Two-time major winners Collin Morikawa and Justin Thomas are among a group three shots behind Henley, along with Patrick Cantlay.
World number two Rory McIlroy made a promising start and reached three under at the turn but struggled on the back nine. The Northern Irishman bogeyed the 14th and 17th, offsetting birdies at the 11th and 15th. He salvaged a smile after a fortunate birdie at the 18th, where a misjudged wedge shot out of the greenside bunker bounced off a stand and rolled back onto the green. McIlroy then holed a 17-foot putt to card a round of 66, leaving him in a tie for eighth.
England’s Justin Rose recovered from a poor start to finish at one under par, having been three over early on the back nine.
Of the 30-man field, 22 players finished the first round under par. Six were level, while only two, American Maverick McNealy and Austria’s Sepp Straka, were over par.
Due to heavy rain in recent days, the round was played under preferred lies rules, allowing players to lift, clean and place their balls on closely mown areas.