Untidy from Philly Mick.

Three putts on the fourth result in a second bogey in his opening four holes.

Both the American and South Africa's Ernie Els are playing in their 100th major here. Plenty of experience there. If anyone knows how to turn it around...

Rory plays a flop shot out of the thick stuff but it sticks on the bank and he cannot hole the slippery 12 foot putt down the hill so he drops his first shot and is back to level.

Image source, Getty Images

The first of the par threes for McIlroy and up she goes, 132 feet in the air at the fourth hole. It has gone through the green so is he going to be able to play another magical chip from the rough? Fowler is the best of the group, a beauty to four feet and he will have a chance to go two under.

Matt Kuchar came oh so close at the Open last month finishing runner-up to Jordan Spieth.

Can he go one better here and earn his first major title?

Maybe with more of this. The American chips in from off the green at the second to go one under.

Kuuuuuuuuuuch.

What a few minutes for the McIlroy, Rahm, Fowler group.

We saw the first case of the Rory fist pump as that chip dropped. It never looked like missing.

Thorbjorn Olesen is the man they're all trying to catch. He's back in the hutch on four under after this birdie on the 18th...

Ken Brown
BBC Sport commentator

McIlroy is all about confidence. If Rory gets going he is like a train you can't stop.

To save on the putting McIlroy chips in from the fringe grass behind the green for a birdie to put the Northern Irishman one under after three. Rahm and Fowler hole birdie putts so all three playing partners are one under.

For the most part the players have found it pretty tough out there today.

Well, that's unless you're South Korea's Byeong Hun An.

Just as Peter Alliss says on BBC commentary that par is a decent score today he rattles in his third birdie from three holes played today.

What a start!

KP knows...

(And online and on the iPlayer)

Englishman Tommy Fleetwood is in the clubhouse after a one-under round of 70 and glad to be out of there.

He tells BBC Radio 5 live the course is "brutal", with no-let up for five hours.

Fleetwood is happy to relax now and for the rest of the field to toil away in what has turned out to be a sweltering afternoon.

Image source, Getty Images

Meanwhile, compatriot Paul Casey - at two under - is happy with his consistency at the majors the season.

But he admits: "It's all about winning one for me now".

We have a new clubhouse leader!

A birdie on the 18th from Thorbjorn Olesen and that takes the Dane to four under.

An impressive round with six birdies and two bogeys for the 27-year-old.

Rory might have come unstuck on the green, but he has been firing some almighty drives off the tee.

Peter Alliss
BBC Sport commentator

That was a dreadful putt. He was obviously scared of the speed.

Ooooo. Tentative.

We said earlier the greens were quick and McIlroy just nudges the ball down the hill for his birdie putt and it drifts wide.

Not Rory's best effort and he knew it.

Ken Brown
BBC Sport commentator

A massive crowd out with Rory's group, there must be six or seven thousand.

Promising signs from Rory.

He makes a solid par on the first hole and, after a drive straight down the centre of the fairway, on the second he lofts an iron high towards the pin where it stops within 15 feet.

He'll have a good chance of birdie from there.

The Northern Irishman looks relaxed too, stepping aside for a little chat with playing partner Ricky Fowler.

Thorbjorn Olesen bogeys the penultimate hole of his round and drops back to three under, joining clubhouse leaders Gary Woodland, Brooks Koepka and Grayson Murray,

Image source, Getty Images

* indicates a 10th tee start

-3 Woodland (F); Koepka (F*); Murray (F)Olesen (17)

-2 Finau (16); Herman (F) Reed (F*); Casey (F*); Stroud (15); DeLaet (5*)

-1 Matsuyama (F*); Fleetwood (F*); Oosthuizin (F), Day (F); D. Johnson (F*)

E ; Z. Johnson (17*); Grace (3); Scott (2) ; McIlroy (1); Fowler (1)

+1 Spieth (F*); Donald (2);

Selected others

+2 Westwood (17*) +3 Poulter (F*); Stenson (F*); +4 Garcia (F*); +8 Pieters (17); +9 Els (F*)

John McEnerney: #bbcgolf, external Finau a lot of people's dark horse for The Wanamaker Trophy he's a boomer off the tee but so are all the big dogs!

(American Tony Finau shot a solid two-under round of 69 and is just one off the lead).

If you're just joining us, it was an up and down (pun intended) start for Jordan Spieth as he bids to become the youngest man to win a career Grand Slam.

The 24-year-old was one of the early starters and carded a one-over par round of 72.

Image source, Gett