That injury has caused a bit of a delay, which are always words to send a shudder through the system. The leading group are at the sixth waiting for Oosthuizen and his playing partners to finish the par three. At least we don't have any threat of thunder at the moment, the conditions are sunny and calm.

Louis Oosthuizen was given more treatment on that arm injury a few minutes ago after seemingly causing himself some damage hitting from the tree roots on the second. He's still limiting the damage on the course though with five pars so far.

His playing partner Chris Stroud is the only man in the top five under par for his round but has just missed the front of the green with his tee shot on the par-three sixth.

Spain's Jon Rahm is the hottest man on the course right now. He's five under for his round after 14 holes and that means he's into a tie for sixth at -2.

Another man on a roll is Jordan Spieth. A third birdie in a row in the bag and he's making a fine finish to his round. Could he finish under par after I ruled out his chances earlier?

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Remarkably Day's little putt does not touch the hole, the first one he has missed from inside five feet this week. It looked to have hit an impediment of some description, there was a definite bobble. Safe pars for Matsuyama and Kisner. It is still Kisner by one and Mr Matt Henry could be a couple of quid better off in this office.

How's Rory McIlroy doing I hear you ask. Well, unspectacular is the answer. He's reached the turn one over par with two birdies and a bogey. He got the big billing as the favourite on a course he loves at the start of the week but hasn't really threatened the top of the leaderboard at any point.

He said he needed two 67s over the weekend to have a chance. He's going to have to turn it on big time on the back nine to manage that.

A chance to get to seven under for Day, who has been tied third or better after two rounds in each of the last four years at this Championship.

A delightful pitch from the Australian, who has a kangaroo on his ball - the image of a kangaroo, that is. He will have a three foot putt for his second birdie of the round.

Back-to-back birdies for Jordan Spieth! Despite finding the rough on his second shot he's on the green in three on the par five and holes his seven footer for birdie. The American hasn't been at his best today or all week in fact but there's a little Spieth magic late in the round.

Another man with a distinctive putter is Chris Stroud, who looks as though he is anchoring it to his chest but is not contravening any new rules. He birdies the fifth and gets himself into a share of second. He's not one of our three sweepstake players so I trust we'll get a refund if he is leading at the end of the round?

Hello. England's Jordan Smith has driven onto the green on the par four 14th leaving him with a putt a little inside 20 feet for eagle. He starts it way right of the hole, it bobs up over a little ridge before picking up pace and nestling at the bottom of the cup.

Excellent stuff from the 24-year-old from Wiltshire.

26 putts yesterday for Jason Day with that white version of the mallet blade. I would always prefer white to red but it looks a little like a toy car on a stick. Three comfortable pars for the final group at the par three and Kisner stays ahead.

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Peter Alliss
BBC Sport commentator

Matsuyama's a bit ragged so far. He's missed a couple of fairways and a couple of greens. He's just hanging on.

The career Grand Slam looks out of reach for another year but Jordan Spieth has put a spring in his step with a birdie at 14. A lovely chip from the edge of the green set up a seven foot putt and the American made no mistake.

A few holes back Dustin Johnson makes birdie on the 10th to move to three over after the par five.

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A chance for Kisner to go two clear but he misses from seven feet at the third. Remarkably it is his first miss from inside 10 feet all week. Day drops a shot after failing to find the green in regulation and missing a par putt from eight feet. Matsuyama calmly brushes his in to stay seven under.

Both Chris Stroud and Louis Oosthuizen have found the sand on the third hole. No bother though. They both play neat bunker shots with Stroud in particular getting plenty of back spin to make the ball come back to the hole. A par apiece.

No sign of an issue with that arm injury for Louis on that hole. Here's how it happened and the later treatment.

Day has dropped a shot at the third hole in both previous rounds and he and Kisner are in the rough down the left, but Matsuyama is down the middle. The world number three turns and directs a lingering stare at someone who might have clicked a camera at the wrong time.

He does take a long time to complete his swing in fairness and you could take umpteen pictures between backswing and downswing.

Hmmmm. Maybe that shot from the trees wasn't so good from Louis Oosthuizen. He might have done himself some damage. The South African is getting some attention from the physio as through he may have injured his arm.

We'll have to keep an eye on that one.

Another safe two putt for par from Kisner, Matsuyama's 12-foot curling birdie effort misses on the left but Day smoothly brushes his putt into the centre of the cup and joins the Japanese player on seven under.

How close can the group of Paul Casey, Rickie Fowler and Justin Thomas get to the top of the leaderboard on moving day?

All three of them bogeyed the first hole which was not in the script but now Thomas has one back in the third.

That takes him back to -3 while his playing partners both took par.

Four successive pars to start the back nine for Open champion Jordan Spieth and he stays at four over.