Jordan Spieth and Rory McIlroy carded contrasting opening rounds of 72 as Spieth aims to become the youngest player to complete a career grand slam in the 99th US PGA Championship.
Spieth's dramatic Open victory at Royal Birkdale means another at Quail Hollow would see him join Gene Sarazen, Ben Hogan, Gary Player, Jack Nicklaus and Tiger Woods in having won all four majors.
But the 24-year-old American had to birdie two of his last three holes to finish one over, five shots off the lead shared by Denmark's Thorbjorn Olesen and American Kevin Kisner.
In contrast, pre-tournament favourite McIlroy - who has won two PGA Tour events at Quail Hollow - was two-under par for 12 holes before dropping three shots in the next two holes.
TWEET OF THE DAY
"Rory reminds me of Jester scolding Mav in Top Gun: "That was some of the best flying I've seen, right up to the part where you got killed." - @JoelMBeall with an interesting take on Rory McIlroy's round.
SHOT OF THE DAY
The new par-three fourth hole and its sloping green has not proved popular with the players, but the Netherlands' Joost Luiten had no complaints after making a hole-in-one with a six iron from 181 yards. Luiten's tee shot pitched around 10 feet short of the hole, bounced once, hit the flag and dropped, although he went on to shoot 76.
ROUND OF THE DAY
Kevin Kisner and Thorbjorn Olesen both carded six birdies and two bogeys in their rounds of 67, but Kisner gets the nod thanks to three of those birdies coming in the last five holes on hard greens which had already seen a lot of traffic.
QUOTE OF THE DAY
"I can't putt any worse than I did today.'' - Jordan Spieth with a phrase you don't often hear from one of the best putters in the world.
STATISTIC OF THE DAY
"If -4 holds as low score today, it would be 1st time since 2008 that no player shot -5 or better in 1st round of #PGAChamp" - The Golf Channel's @JustinRayGC highlights how difficult Quail Hollow played on day one.
The par-four 16th, the start of the so-called Green Mile of finishing holes, played the toughest on day one, with just six birdies more than cancelled out by 52 bogeys, 10 double bogeys and two triples. That meant a scoring average of 4.462.
In contrast the 577-yard 15th proved the easiest, with six eagles, 60 birdies and just a solitary double bogey leading to a scoring average of 4.609.
READ MORE ON PGA CHAMPIONSHIP:
ON THE UP
The prospects of a second consecutive home winner after American players filled 12 of the top 14 places on the leaderboard, with only Denmark's Thorbjorn Olesen and England's Paul Casey breaking up their dominance.
ON THE SLIDE
Brooks Koepka's reputation after the US Open champion failed to shout the traditional warning of "Fore" when his drive on the 16th was heading into the crowd. It hit a marshal on the head, knocking the man to the ground and leaving him bleeding from a head wound.