Thorbjorn Olesen and Kevin Kisner matched each other with long, curling birdies at the final hole to share a one-stroke lead as Jordan Spieth slipped five strokes off the pace after the first round of the PGA Championship in Charlotte, North Carolina on Thursday.

On a day when many of the favourites started well, Dane Olesen and American Kisner carded four-under 67, one better than a group including US Open champion Brooks Koepka on a Quail Hollow course that bared its teeth despite a mere zephyr of a breeze.

Spieth, at 24, seeking to become the youngest man to complete the career grand slam after winning the British Open last month, struggled on the newly-grassed greens and needed two late birdies to salvage a 72.

Pre-tournament favourite Rory McIlroy also laboured to a 72 after finding water with his tee shot at the driveable par-four 14th.

Soft fairways and rock-hard, ultra-fast greens yielded some major casualties, none more so than five-time major winner Phil Mickelson, whose 79 was his highest ever score in 95 rounds at the PGA Championship.

Spieth said he could only improve on his slow start.

"I can't putt any worse than I did today," said the Texan. "I don't think I missed any short putts today. I just had really poor speed on my long ones."

Jordan Spieth, PGA Championship 2017, first round
If he is to break to record, Jordan Spieth is going to have to play a lot better in the final three rounds, August 10, 2017Reuters

Co-leader Olesen offered a pretty good formula to explain his sizzling start.

"The first 15 holes, especially, I was driving the ball very, very well, and that made it a bit easier," said the world number 78, a four-time European Tour winner.

"Coming in with some short irons into these greens was definitely the key to the round. I felt like I gave myself a lot of opportunities, and it was a very, very nice way to finish with that long putt."

His 25-footer at the par-four 18th was no less impressive than the closing birdie by Kisner, whose sharply-breaking 20-footer tracked in dead centre.

"There are about four or five holes I have to birdie to compete and I birdied them all today," said South Carolinian Kisner.

Among the big names who hit the ground running, American Dustin Johnson, Japanese Hideki Matsuyama, Spaniard Jon Rahm and Australian Jason Day all carded 70.

"This is a really good start," said world number three Matsuyama, who birdied his final three holes, including a 50-footer at the last that he called a 'bonus'.

McIlroy lamented his poor tee shot that led to the double-bogey but was even more disappointed to duff his chip.

"I still could have made a par. I just didn't execute it properly," said the Northern Irishman.

Get the full leaderboard of the first round