Phil Mickelson is in trouble off the sixth tee and is hitting a provisional ball and Zach Johnson is knee deep in rough searching for his ball on 12. Johnson has an army of helpers and five minutes to find it, it's like the Crystal Maze.

Image source, BBC Sport

Oh that is a thing of beauty. All of 25 feet, right to left, up a slope, then left to right - bingo. Danny Willett makes eagle on 10 and is five under, two off the lead.

What can Mickelson and Stenson do on five? Birdies apiece. Mickelson hits a poor eagle putt but sinks the return nicely and is already three under.

One man who is seeing his day turn mildly sour is Paul Kinnear. The amateur is now two under after some bogey action. Five under for his front nine, three over for the back stretch so far.

Mickelson pumps one up at the fifth way. None of this stop and spin malarkey here though at St Andrews. It bumps, runs, rolls and... he'll take that. Probably around 15 feet for eagle.

Can Henrik Stenson better it? Remember he has no win in a major. A sumptuous seven iron and that leaves around 10 feet for what would be eagle and big leap into red numbers.

Elsewhere, Zach Johnson - Mr Steady - moves to six under. No fireworks, just plod, plod, putt, putt.

Image source, Getty Images

Justin Rose has plucked the wraparound sunglasses out of his bag. Not to combat the St Andrews sun though, more to stop his eyes being irritated by pesky insects and dust picked up by the wind. Any hayfever-suffering golfers will feel his pain. 

The Englishman's opening gambit on four lands inbetween Rickie Fowler and Nick Faldo, whose tee shots are a whopping 62 yards apart. The ageing process, technological advances or both are probably the reason why...

Rose jigs around the green after seeing a python-length putt rattle into the can, Fowler misses one half the size for his birdie, while Faldo - with his unorthodox reverse putting grip - drops a shot from shorter than the aforementioned reptile's forked tongue.

Thanks for this one Samm, a belter. 

Please keep sending us your best/worst efforts for fashion on the course to #bbcgolf.

An Englishman is in the clubhouse at four under for the day and his name is David Howell. A couple of bogeys on the back nine will anger him but on the whole, lovely stuff. His final putt for par is eight feet and it rattles around the cup, easily done.

This links golf is supposed to be hard? There is widespread assault against this course on hand today.

Image source, BBC Sport

Par, birdie, par, birdie... Phil Mickelson drains a delicious putt from 15-20 feet. It breaks right to left and it's judged to perfection. A touch of his cap as the claps tumble his way. 

The Open flag flutters a great deal on the pins now, conditions are becoming testing and to be comfortably in red numbers after four holes - 'Lefty' will be thrilled.

Now then, the 'Wild Thing' on the 10th. This man is dressed brightly and he's shining on the dance floor too, another birdie.

John Daly of course won this competition in 1995 and at four under through 10 why not again?

His latest putt is a snake from six feet - in you go sunshine.

You don't lose it! Bernhard Langer - that mild-mannered, human embodiment of stereotyped German efficiency - sees his ball disappear down the St Andrews plughole for a fourth birdie in his opening six holes. 

Another late 1980s/early 1990s warhorse, Sir Nick Faldo, is unable to step into a time machine like his Ryder Cup team-mate though. The Englishman slides a birdie putt wide on three, he sticks on +1.

Image source, Getty Images

Stephen Gallacher sinks another birdie putt as he moves to three under after five. Good news for anyone who had the Scot at 250/1 before the tournament started...

Jordan Spieth, who is seeking to win his third major of the year, speaking to BBC Two: "I played the front nine exactly how I mapped it out. We did some good preparation but if the wind changes direction it could be a completely different course. Tomorrow it will be the same course but with the wind l will have to keep the ball lower. It will not be a birdie fest on Friday though."

Image source, Getty Images

Zach Johnson is on the charge. The American rolls in for birdie on nine to move to five under. Can the 2007 Masters champions challenge here?

American Dustin Johnson speaking to BBC Two: "Any time you shoot 65 it's very pleasing. I played well and conditions got tougher. When you turn around and come back into the wind it's more difficult. I got out or position a couple of times but managed to save a couple of pars and I had close looks at birdies all day. At Chambers Bay for the US Open I played well, did everything I was supposed to do, but it's tough when you hit good putts and doesn't go your way. I've moved on from that now for sure."

Rickie Fowler, bushy eyebrows peeking out under his dark blue baseball cap, smirks as he walks away with a second successive par. A bit more gusto on his birdie putt and he would be in the red. Justin Rose is beating that old rogue par, backing up his opening birdie with another hold on the 452-yard par-four second. Nick Faldo - playing in his last Open - wraps up a clean sweep of pars.

Image source, Getty Images

More joy for the Scots as Marc Warren goes out in four under... It's looking good for the hosts... compatriot  Richie Ramsay is on three under.