Viktor Hovland joins Ryan Fox at the top of the leaderboard with a wonderfully controlled 10-foot putt for birdie on the fourth.

This has been a fine opening round from the Norwegian who came close to his first major at last year's Open, remember.

Jordan Spieth holes a six-footer to salvage par on the same hole.

I'll be writing a full and frank apology to Ryan Fox for calling his birdie putt a gimme moments ago as he's only gone and missed it!

It's only about two feet or so and to be fair Fox put a seriously dodgy jab of a stroke on it, but I can't help feeling partly to blame for that one....

The sixth hole has been the hardest on the course today so Scheffler takes no chances after finding the bunker off the tee.

He lays up and then plays a splendid shot just past the pin. Another comfortable par looming.

Koepka is going bunker to bunker and will need to get up and down from the front of the green to save par.

Ryan Fox is feeling it now down the stretch, and he comes ever so close to holing his second shot for eagle at the tough 16th when he takes dead aim from 119 yards and almost sinks it.

The ball lands close to the pin and actually catches a piece of the hole, but lips out with too much pace or a bit of extra sauce on the ball from Fox.

A great shot though and leaves him a gimme birdie putt that even I'd make.

Is the Big Mo with McIlroy? The 34-year-old sends his eagle attempt racing down towards the cup. This needs to pull up and does after just sliding by on the right, with Rory McIlroy then tidying up for birdie.

Justin Thomas has a short one for his four but rolls it over the left edge before making certain of his par.

Meanwhile, Collin Morikawa scrambles superbly from the sand to give himself a look at birdie from eight feet, which he duly sinks.

Hello Scottie.

The world number two has ticked his round over but finds some juice on the fifth hole to dig out a second birdie of the day from 14 feet.

It leaves him within one of leader Ryan Fox.

Sadly for Koepka, it's a two-shot swing as he's hampered by a perilous uphill lie in the rough and he overshoots his chip.

A long-range putt follows - and misses - and he is forced to suck up a bogey and a move back into the blakc.

Matt Fitzpatrick seems to have arrested his slide. Another regulation par on the second. Fairways and greens. Fairways and greens.

Cam Smith lets another one slide though. A three-putt from 55 feet, with a seven-footer for par sliding by.

Oh my that is some shot. Rory McIlroy has some 259 yards to the pin on the 617-yard fourth but creams his second right into the middle of the green to leave and eagle putt from around 22 feet.

Justin Thomas is up next and having laid up with his second lofts a glorious wedge that spins back off the turf to leave himself with a tiddler for birdie.

Collin Morikawa's second thumps into the sand down the right.

Woah! Jon Rahm airmails the second green and the bounce sees his ball scud through into the cabbage. And then he's tentative with his next, the ball trundling back down the slope towards him.

He's now in Rory McIlroy territory. Can he repeat the Northern Irishman's sensational par saver? Nope. Not even a sniff. He tidies up for bogey. His fourth in five holes.

He was red-hot favourite at the start of play... long way to go yet though.

That's more like it off the tee from Scheffler.

Picking up his iron for the newly-created par-three fifth, he fires a terrific tee shot into the middle of the green.

Koepka tries to match him and just misses left, but is grateful to see his ball stop dead in the rough rather than cascade into one of the steep bunkers that flank this green.

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Jordan Spieth loves nothing more than a good chat with his caddie Michael Greller and he's casting him a long look after missing a 15-footer for par on the third. There's a bit of an arm wave and then a wry smile.

He's not quite at the races today.

Neither is Shane Lowry. He plays an extraordinary flop shot with the hole no more than 30 feet away. He makes a mess of that and the ball threatens to tumble off the front edge of the green. Bogey.

Viktor Hovland is going along well though. A two-putt par keeps his momentum going.

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Outstanding recovery from Scheffler. After that wayward tee shot and lay-up, he plants his third into the bunker but only goes and flicks it out to within three feet. Daylight robbery for him to come away with a par.

Koepka has a chance to get in the red with a birdie putt from 14 feet. However, once again it slides by and he has to settle for a five.

There is some good news for Woodland at last though. He picks up a birdie and moves up to +4.

Is this another sign things are improving for Rory McIlroy..

The world number three finds only his second fairway of the day on the fourth hole (his 13th).

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Simply sensational from Rory McIlroy...fresh from the sublime par save he knocks his tee shot on the par-three third in to two feet. It's birdie time for Rors.

Just pars for Collin Morikawa and Justin Thomas, who do well to get up and down from opposite greenside bunkers.

I've been waiting for that headline..

And Ryan Fox deserves it, after he carves his tee shot at 14 miles right, seemingly dead, but plays a super recovery to within 15 feet and obviously then goes and rolls it in for the most unlikely of birdies.

It also takes him into the outright lead!

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Matt Fitzpatrick knows how to grind. He did so superbly to win his US Open title last year. And he went close at last year's US PGA.

The Englishman needs a bit of that on his back nine today to keep himself close. A straightforward par on the first is just the ticket.

Jon Rahm also steadies the ship with a simlar par.

But Cam Smith can't complete the set. He was way left off the tee and paid the price, missing an 18 footer for par.

A bogey to start his back nine was a bit of a kick in the guts, but Corey Conners has recovered since then and takes advantage of the short par-four 12th hole with ripper of an approach from 101 yards to stick it inside a foot.

Tap-in birdie time to get Conners back into a share of the lead.

Scheffler finds himself flush behind a tree and is forced to clip out onto the fairway. Still 216 yards to go for the world number two.

It's a better lie for Koepka who can make more progress towards the hole. He's got 121 yards left for his third shot.

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Viktor Hovland is trending well. A super 17-footer across the second green catapults him to the top of the leaderboard.

The Norweigan was two over after three holes. Four birdies since have changed his fortunes.

Shane Lowry makes a decent par save but Jordan Spieth misses a terrific opportunity to claw a shot back, missing a six-footer.