Pain-free and relaxed is our man Iain Carter's assessment of the world number one. Some other onlookers agree, some disagree...

Iain Carter
BBC Radio 5 live at Augusta

Image source, PA

 A smiling Dustin Johnson has just arrived on the range and is gradually working through his irons alongside his coach, Butch Harmon.

The image you get from the world number one is that he is pain-free and relaxed. Wearing a dark green top, a white cap and white trousers he's chatting away with his caddie, brother Austin. 

The acid test will come when he starts hitting longer clubs - but the first impression of Johnson is that he's suffering no ill-effects from the fall that hurt his back last night and he's ready for business at this year's Masters. He's off at 19:03 BST.

Talking of nerves, a few will be jangling around the Dustin Johnson camp. Not to mention those punters who have stuck some money on the world number one.

We've spotted him! He's on the practice ground... 

...and that means he is now two shots off the lead.

Leader Thomas Pieters, in the group behind Sullivan, drops his first shot of the day. All looks swell as the Belgian finds the middle of the green on the 11th, in regulation, only to three putt for a bogey.

Jingle jangle...

Another dropped shot for the defending champion.

Danny Willett leaves his par putt agonisingly short from 22 feet and has to make do with a bogey on the par-five second.

He's three over through the opening two holes.

The sort of putt that Andy Sullivan knocks in with his eyes closed. But this is Augusta. Pah! No bother. The Englishman confidently cans his short birdie putt on the 12th to go two-under...

Anyone else humming the Reservoir Dogs theme tune?

Torture.

That's what these first couple of holes will have felt like for Danny Willett.

His tee shot on the second also finds the rough stuff and then it's straight into the sand for the defending champion.

After scrambling out of the bunker, Willett puts his approach into the heart of the green, 22 feet from the pin. Can he salvage par?

-5 Thomas Pieters (after 10 holes)

-2 Rickie Fowler (9)

-1 Andy Sullivan (11), Phil Mickelson (8)

Selected others: E Jordan Spieth (9), +1 Jason Day (7)

The rest of the tee-off times  can be found here , or find out more about the  BBC's coverage here.

Image source, Reuters

Andy Sullivan has been dubbed the Smiling Assassin. Well, he's certainly smiling. And he's just taken out the iconic 12th hole with a bullet of a tee shot.

The Englishman walks over Hogan Bridge safe in the knowledge that a two-foot birdie putt awaits...

Plenty of big names are already out on the course, plenty more are still on the practice ground.

Here's who you need to keep an eye on over the next hour or so...

18:19  - Sergio Garcia (Spa), Lee Westwood (Eng), Shane Lowry (Ire)

18:30  - Bernhard Langer (Ger), Alex Noren (Swe), Patrick Reed

18:41  - Rory McIlroy (NI), Hideto Tanihara (Jpn), Jon Rahm (Spa)

18:52  - Marc Leishman (Aus), Bill Haas, Justin Thomas

19:03  - Bubba Watson, Dustin Johnson, Jimmy Walker

Image source, Getty Images

While we're on the subject on men called Johnson, we're still none the wiser about Dustin's whereabouts.

Once we know, you'll know.

Although how a lanky bloke gingerly walking around Augusta with his hand on his back is inconspicuous I don't know.

I hope Zach Johnson put a ball retriever in his bag. He's spending more time in the wet stuff than a koi carp.

The 2007 champion goes for broke on the 13th, only to splash into the tributary to Rae's Creek which snakes in front of the green.

Meanwhile, another Green Jacket-owner is also in the black. Adam Scott bogeys 11 to drop back to +2.

Oh dear. That's not how Danny Willett would have envisaged starting his Masters defence.

After sending his tee shot deep into the trees, it took the world number 17 two strokes to salvage a spot on the fairway.

Willett then two-putted on the green to kick off with a double bogey.

His 2017 tournament might have peaked at the champions dinner...

Image source, Getty Images

Seeing the sign pointing towards Amen Corner can strike fear into the minds of even the world's best golfers. 

Just ask Jordan Spieth. Or Rory McIlroy. Or Greg Norman.

Amen Corner, a term coined by legendary sports writer Herbert Warren Wind in 1958, strictly refers to the 11th, 12th and 13th holes, but many also tend to include the notoriously difficult 10th. 

"If you can get through those in level par you're a happy man," says BBC golf commentator Ken Brown.

Somebody put the brakes on! Thomas Pieters is threatening to run away with the Augusta lead. 

The Belgian sinks another birdie on the par-four 10th - his fifth of the morning - to go four shots clear.

Not a bad advantage going into Amen Corner...

England's Scott Gregory, who won the 2016 Amateur Championship to book his place at this year's Masters, 

The 22-year-old opened with a triple bogey and has matched that on the short 12th, without dipping his toes in the water that ruined Jordan Spieth's title hopes last year.

Gregory fired his tee shot long into the azaleas, barely moved his ball with his second swing and then three-putted from short-range. He's propping up the field on +7.

Phil Casey of the Press Association believes we are getting worked up for little reason on all things Dustin Johnson.

What's that? Is there any news yet on Dustin Johnson? I hear you.

But unfortunately we haven't got any official news yet. Augusta is playing one massive game of Chinese whispers at the moment...