Scheffler puts from the fringe and it's an ideal line but his ball loses momentum up the hill and stops short. A ninth par of the day and he stays at one under.

Koepka rolls his third to seven feet and keeps his nerve to sink for par.

No fireworks from these two but par is a good score on this course so they're ticking along.

Another excellent tee shot from Scheffler and he picks out his wedge to take on the first green. He's left disappointed though as his ball rolls back off the putting surface.

He'll have a choice to chip or putt - as will Koepka who has 50 feet and two shots to get par.

The Oak Hill Country Club sounds idyllic - but some of these holes are already causing hiccups!

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Rory McIlroy sends a wild drive towards the tents lined up on the right of the 18th hole.

The Northern Irishman looks like he is fuming at that and swipes at fresh air with his driver in frustration.

Looks like he's found the sand there and he can only lob his second some 50 yards on before launching his third in towards the green and benefitting from a lovely kick off the left hump to run into around 18 feet.

Big par-saving putt coming up.

Cam Smith is rumbling along nicely with another decent par save on the 16th. After launching his tee shot into a fairway bunker and only advancing his ball to a few yards short of the green from there, he takes two more from 90 feet, draining a six-footer for his par.

A big par putt for Matt Fitzpatrick too. Coaxing one in from seven feet to avoid a third successive bogey.

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Stunner from Theegala who drills a long iron to this monster par three, coming in at 248 yards today - that's a solid driver (and then some) for most of us.

This is an arrow though that is right at the 11th flag, lands short and heads towards the cup, just pulling up a couple of feet shot of what would be an incredible ace at this hole.

You'd be surprised if anyone manages to take this nearest the pin prize off Theegala, as he taps in the birdie putt to join the leaders.

Over on the 16th and Jon Rahm is in a bit of trouble, pushing his drive into rough and tugging his second even deeper into trouble.

His third isn't much better, pitching too far onto the green and racing 15 feet past the hole. Big putt coming up. Can't hole it. First dropped shot of the day.

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Disappointment for Scheffler who misses out on a birdie with a wayward putt.

It's been a precise front nine from the world number two but his putter has been cold recently - and he's two shots back at the halfway mark of the first round.

Koepka goes closer to a birdie, but his ball kisses the lip and rolls on. He'll head to the back nine at level par.

Woodland will be received to see the back of that hole as they move on to the first tee.

Jordan Spieth stares to the heavens and flips his club in the air - neatly catching it on the way down - after a birdie putt from just off the 17th green lips out.

It looked in all the way.

Viktor Hovland comes up short with his effort from around 20 feet. Pars for both incoming.

Big things are expected from Sahith Theegala, who is playing alongside US Ryder Cup captain Zach Johnson in what could be an audition for Rome - and he's playing nicely.

Theegala closed out his front nine with successive birdies - the second of which coming via a chip-in from off the edge of the ninth green from 40 feet.

That kind of stuff will grab Johnson's attention alright

Rory McIlroy is toiling here.

The four-time major winner just can’t hit a fairway at present and it catches him out on the 17th. After drifting well right off the tee, his second finds the left greenside bunker and can't get up and down from the sand. That's couple of strokes shipped in three holes.

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Magic from Scheffler as he dinks a delicious iron shot into the heart of the green. He'll have a seven-foot putt to close the back nine with a well-earned birdie.

Meanwhile, Woodland has taken a drop and is next to the road, surrounded by punters and sizing up two giant trees that block his route to the flag. He's almost crunching his backswing against the steps of the hospitality tent behind him.

And wouldn't you know it, he sails his shot out of trouble and onto the green. Well played Gary.

It's a narrow fairway on 18th but Scheffler's tee shot just squeaks over the bunker and lands neatly in the short grass. Koepka joins him in an ideal position to attack the flag.

The third member of the group Woodland though is in serious trouble off the tee, skewed right and next to the hospitality tents. He tries to dig it out but whacks into a tree and he's off to look for it.

Woodland by name...

How about that for a recovery. Rory McIlroy gets down from 80 feet in two to save his par on the 16th. Pars all round given JT can't sink a 15 footer.

Magical from Cam Smith from a greenside bunker on the short 15th. He shouldn't really be in there in the first place given the hole is only 163 yards but he went chasing the pin and short-sided himself.

A full swing and a caress of the ball out of the sand leaves him eight feet to save par. Nailed.

Jon Rahm is eyeing up a birdie from 32 feet after finding the centre of the green. Two putts needed. Par. His fifth in a row after that opening birdie.

Can Matt Fitzpatrick claw a shot back here? He's also 30 feet or so from the hole. Down in two.

Two hours for six holes... hope you've all got plenty of snacks in.

Tarren avoids the water on the sixth and chips up out of the rough, perhaps a little cautiously, but his shovel-like attempt at a par putt costs him a shot.

After three birdies in a row, back-to-back bogeys slip the Englishman down the order.

It's a good effort from Koepka who goes for glory from 23 feet. It's close but fails to trouble the cup.

Similar for Scheffler who thinks he's got the right line but it does not quite turn enough and skips past.

He'll have to settle for his seventh par in eight holes.

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2011 US PGA champion Keegan Bradley has made a flying start with three birdies in his first four holes to grab a share of the lead.

The 36-year-old hits a beauty of a long-range putt from 32 feet that snaked across the 13th green and was always tracking from right to left before smacking into the back of the cup.

Rory McIlroy has been a little erratic off the tee so far and it is really undermining his scorecard.

His drive on the 16th is a little wayward, drifting left and it means he can't find the dance floor with his second.

The pace of play, by the way, GLACIAL. Fitz, Smith and Rahm teed off at 15:23 BST. One hour 45 minutes for five holes.