Sinking this will provide a bit of breathing space for Justin Thomas. He must negotiate a sharp left-to-right swing... he thinks he's got it... no! The ball drifts away from the hole as Thomas drops to his haunches.

A one-shot lead will have to do...

Matsuyama rattles one into the back of the cup at the par five from 12 feet and he joins Reed in a share of second, one behind Thomas, who has the Green Mile ahead. The 16th is playing the third hardest hole this week and the 18th is the hardest. Who is going to handle it best? We're about to find out.

Leader Justin Thomas on 15... after that ripper of a drive he pulls his approach slightly left.

A gentle clink of the wedge sees his ball fly over the bunker and hit the top of the slope. But the ball doesn't go though - as the waving arm gestures from a slightly twitchy Thomas tells us.

A ten-foot putt awaits...

We're not seeing much of the final pair now because they have not been the main contenders recently. Stroud sees a birdie opportunity slide by but Kisner gets the golden flat stick working again and he's back to six under, two adrift.

Matsuyama is no stranger to taking his hand off the club. Often the ball still sails down the middle or onto the green but this time it is into the human herbaceous border on the right of the dance floor at the 15th.

No wonder he mops his brow in careworn fashion like Bernard Manning. He is two behind Thomas.

Image source, Getty Images

Iain Carter
BBC Sport golf correspondent

Molinari has had a fantastic week. We haven't seen the Italian on too many leaderboards this year.

Never in doubt. Another sandy save from Francesco Molinari on the last sees him finish on six under. The Italian, who sunk four birdies in his seven holes home, is our clubhouse leader...

Justin Thomas is flying. And so is his ball. Our glorious leader spanks his drive on the par-five 15th for a 322-yard carry, his ball grinding to a halt on the fairway in a perfect position on the right-to-left dogleg.

Here's how he grabbed the outright lead a few moments ago...

Jay Townsend
Golf expert on BBC Radio 5 live

You could have a two-shot swing on any of the last five holes. This is about execution right now - it doesn't matter what you've done in the past.

Let's just remind you of the very latest, it's Justin Thomas ahead at eight under, one ahead of fellow American Patrick Reed, two fellows without a major in their collection.

Peter Alliss
BBC Sport commentator

Nobody's out of it if those sorts of things can happen for Oosthuizen.

There's a huge roar from somewhere over yonder... turns out it is from the 15th green.

That's because Louis Oosthuizen has just chipped in for an eagle. The 2010 Open winner moves up into a share of third place on six under.

A magnificent pitch to inside two feet at the short, 344-yard par four 14th and it's a much-needed birdie for Matsuyama, who is two behind playing partner and outright leader Thomas.

Justin Thomas can do no wrong with the short stick at the moment. He's a club short of the 14th green... it might not matter. The world number 14 gives his ball a shove with his putter... he's not done it again has he? Nope. His ball meanders right, leaving him with a tap-in to save par.

Francesco Molinari liked the sand so much on the 16th that he's decided to have another play in it on the last.

The Italian tugs his drive and could have buried his hopes of a first major.

Where has Patrick Reed sneaked up from? A birdie on the 14th has lifted him above a couple of names who were leading not so long ago.

The American knocks an eagle chip on the par-five 15th within a few feet, converting for back-to-back birdies.

He's just grabbed hold of second place.

Image source, Getty Images

That immaculate Kisner putting stroke is not holing them anymore. It's back-to-back bogeys and he too is three back at five under. That stat about 18 of the last 20 winners coming from the final pair is going to widen it seems...

As Thomas strikes a key blow, Matsuyama, having seen his chip stop stone dead, misses from 12 feet for a par and drops another shot. He's only five under and that is three shots behind now.

Maureen Madill
BBC golf commentator

Oh my goodness it's in the hole. That was a killer blow from Thomas. There's a bit of daylight now between him and the others

Justin Thomas pushed his tee shot on the par-three 13th to the fringe on the left. What can he do from here? He's got a wedge in his hand, not a putter.

It doesn't matter! He's only gone and holed it. What a touch.

Thomas is two shots clear.