|US PGA leaderboard, round one|
|-4 Olesen (Den) Kisner (US); -3 Murray (US), Koepka (US), Woodland (US), Stroud (US), Points (US)|
|Selected others: -2 Reed (US), Casey (Eng), Fowler (US); -1 Matsuyama, Fleetwood (Eng), Smith (Eng), Day (Aus), D Johnson (US) Rahm (Spa); Level Scott (Aus), Kuchar (US); +1 Wood (Eng), Spieth (US) McIlroy (NI); +2 Willett (Eng), Westwood (Eng), McDowell (NI); +3 Poulter (Eng); +4 Garcia (Spa), +5: Rose (Eng), Donald (Eng); +8 Mickelson (US)|
Rory McIlroy and Jordan Spieth are both five shots off leaders Kevin Kisner and Thorbjorn Olesen after the first round of the US PGA Championship.
Spieth, 24, made two birdies in his last three holes to card a one-over-par 72 as he bids to become the youngest player to win the career Grand Slam.
McIlroy hit the same score despite reaching two under after 12 holes.
Grayson Murray, Brooks Koepka, Gary Woodland, DA Points and Chris Stroud are all one shot off the lead.
World number 78 Olesen was among the early starters at Quail Hollow and hit six birdies, including one on the 18th hole which took him to four under and into the outright lead.
The Dane held that advantage until late in the day's play when American Kisner also birded the 18th to complete a round of 67.
England's Paul Casey is the best-placed British player, tied for seventh on two under par.
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McIlroy threatens and then falters
Despite being without a tournament win this season, Northern Ireland's McIlroy was installed as the pre-tournament favourite at Quail Hollow, where he has won twice on the PGA Tour and holds the course record.
After two opening pars the 28-year-old brought his round to life by chipping in from the edge of the green for birdie on the par-four third.
McIlroy followed that with two bogeys in three holes, but birdies on seven, eight and 10 took him within two shots of the lead.
However, the round stalled when, after a bogey on the par-three 13th, McIlroy hit his tee shot into the water hazard on 14 and made a double bogey.
"If someone told me I would shoot one over par this morning I probably wouldn't have taken it, but the course played tricky," McIlroy said after recovering to finish with four straight pars.
"It would have been nice to shoot under par but I played a three-hole stretch on the back nine three over par. That was the only thing that derailed my round."
McIlroy was playing with best friend Harry Diamond as his caddie after he split with long-term caddie JP Fitzgerald last month.
BBC golf expert Ken Brown
A one-over-par 72 was not bad overall for Rory McIlroy. The afternoon players had it slightly tougher, with the wind getting up.
The greens were super fast. Judging the line and pace was tricky.
Late birdies give Spieth steady start
The US PGA is the only one of golf's four majors Spieth is yet to win after victory at The Open last month.
Victory for the American - who was Masters and US Open champion in 2015 - would see him surpass compatriot Tiger Woods as the youngest player to claim all four majors.
He turned 24 four days after his triumph at Royal Birkdale, while Woods was 24 years, seven months and 25 days when he completed the career grand slam by winning The Open in 2000.
Spieth started his round on the back nine with five straight pars before a birdie on the 15th.
He then made bogey on the par four 16th, the first of the fearsome three holes named 'the Green Mile' on the North Carolina course.
Another three bogeys followed on the front nine before a birdie-birdie-par finish to close on the leaders.
"Given it's the first round I know I'm still in it, but I know that tomorrow's round becomes that much more important to work my way and stay in it. I've got to make up ground," Spieth said.
'Green Mile' eats up Garcia - plus the rest
The final three holes at Quail Hollow measure 1,223 yards in total and have developed a reputation as one of the toughest closing stretches in golf.
Masters champion Sergio Garcia was the first to struggle there on the opening day, dropping five shots on the 'Green Mile' - although the Spaniard steadied on the front nine to finish on four over par.
Garcia was playing alongside Spieth and US Open champion Koepka, the trio making up 2017's major winners so far.
American Koepka fared best with five birdies in his round of 68 leaving him one shot off the lead in a tie for second.
England's Tommy Fleetwood and Jordan Smith both finished at one under as the best placed Britons behind Casey.
Fellow Englishman Justin Rose had played a steady round until five dropped shots in the final six holes meant he slipped back to five over par, while compatriot Lee Westwood carded a 73.
Andrew 'Beef' Johnston withdrew from the tournament with a shoulder injury after a seven-over-par 78.
American five-time major winner Phil Mickelson had a torrid day, shooting an eight-over 79 with eight bogeys and no birdies.
|US PGA Championship 2017|
|Venue: Quail Hollow, Charlotte Dates: 10-13 August|
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