Defending champion Collin Morikawa won't be going back-to-back.

He's just rolled in a short par putt on the last to sign for a two-over 74.

A mix of four bogeys and two birdies.

Ooohh, where's that Phil Mickelson approach gone? It drifted left off the bat and disappeared beyond a bank, might be some sand down there, he'll hope so.

Louis Oosthuizen is in the same spot, so Mickelson has to take his ball and be careful not to clean any of the sand off it, before replacing.

Lovely clip out of the sand from the South African, dashing up the bank to watch it run towards the flag. Now for Lefty's turn... there's a bit of chat beforehand about where he pops his ball. A quick rake to recreate the exact lie and then the American flops it out to within a few feet. Smart.

DIsappointing bogey to end the front nine for Koepka - a drive into the right rough then a tugged approach into the left 'sandy waste area' does the damage and he drops to four under.

Grace manages a par four and he reaches the turn a shot ahead of his playing partner.

Maximum points for Guy.

We asked you - can you name the 21 US states that have hosted this championship, with bonus points if you can add the course and winner... #bbcgolf with your answers and a selection will also be read out on the radio

Hideki Matsuyama made his move on the back nine in the third round at the Augusta National just over a month back.

Here he's having to produce some scintillating golf even earlier just to stay in touch with Phil Mickelson. How long can it last?

Not for the first time today he makes a scrambling par after a wayward second flew left of the green. That'll do nicely.

That's a bad miscalculation from Christiaan Bezuidenhout. The 27-year-old overshoots the green with his second and then can't get back in two after finding the longer stuff down the right side.

Phil Mickelson finds the green on the par-three eighth but this is a long'un - you need a degree to read one of these topsy turvy Pete Dye greens from there.

Lefty has a BA in holing crowd-pleasing putts and this is almost another from distance, ducking and diving its way across the short stuff, but it puts the brakes on a tad short. He'll take par.

Louis Oosthuizen bounces back from that unforgivable missed birdie putt at the last by knocking one in here and that moves the South African to five under. He's still right in the mix.

Impressive stuff this from Grace, as he dunks an 18-footer for a two on the eighth, breaking that yo-yo run and making it back-to-back birdies.

Excellent iron shot off the tee to set that up and having had his problems he's been really strong mentally to keep going. He's well in this fight for the title.

Koepka actually does well to make par here with that five-footer a bit of a knee knocker given the short one he missed on the sixth.

Hideki Matsuyama is motoring. I wonder the roars behind him are inspiring the Masters champion.

He drops a superb tee shot to three feet of the pin and tidies up nicely. That's three birdies in five holes. He's now tied for second.

At one stage on Friday Jon Rahm was flirting with the top end of the leaderboard but he finished poorly to record a 75.

And the Spaniard also seems a little underwhelmed by going round in par today.

Louis Oosthuizen has shown a really nice touch from the sand today, but the main event is his playing partner in the final group...

Phil Mickelson has an eagle putt at the par-five seventh to get to double figures. It starts left and breaks right just a touch, but flirts with the cup and stays up. Birdie it is instead.

Oosthuizen, meanwhile, after a delicious bunker shot, flunks a tap-in birdie chance and misses the chance to climb to five under.

Talk about an up-and-down round! Grace gets another birdie to get back to four under and that's now a bogey-birdie-bogey-birdie run - bogey on the next then!?

Koepka also takes advantage of the par five with a birdie of his own to get back to five under and in second behind Mickelson.

A Lefty bomb down the seventh fairway, some 319 yards with 234 to play. Mickelson flights it high in the South Carolina sky and creeps on to the green. Eagle chance for the leader...

Brad Marek is one of 20 club professionals who have teed it up this week at Kiawah Island. His stretching exercises on the range have been a sight to behold.

The Californian was one of two who made the cut and he was rattling along quite nicely today at one over for his round... until he reached the par-three 17th.

He took the sensible option that many others have by hitting away from the water and into a greenside waste bunker. But then his troubles began.

He pitched his next shot into the water. Penalty drop back in the sand. Fourth shot... into the water again. Sixth shot from the sand... on the green and two putts for an eight.

Still, bet he's having a belter of a week.

Great save. Hideki Matsuyama must have ice running through his veins.

A lob on leaves him with loads of work to do but he knocks in 15-footer to make his par.

Not that the TV coverage picked it up but Christiaan Bezuidenhout played a superb little chip to three feet and then converted for a birdie. His first of the day.

Funny old round for Bryson, he's not really doing anything wrong but can't get anything going - if anything he's playing steady away but unspectacular.

That's not what we expect!

Louis Oosthuizen is in one of the bunkers flanking the sixth green but shows a delightful touch to flick it out to within a few feet. Should be par.

Phil Mickelson is locked in today. He sizes up a birdie putt from 17 feet, sets it off and watches it track all the way into the cup, just dropping in the side. He's out to eight under par. Magnificent.

Lefty goes four clear of the field.

Hideki Matsuyama has looked okay out of the sand so far today. So what will he conjure up here after putting himself in trouble off the tee?

Nowt much. After the big up, he hoiks it forward about 50 yards. Must have had a pretty poor lie. His third doesn't quite carry to the green. This could be a problem. There's a fair few contours around there and he's running short of shots to save par.

Phil Mickelson finds the rough with his tee shot at six but that is no issue when he's in this form as he dices an approach into the middle of the green. A quick look and then a stride off towards the dancefloor with brother and caddie Tim in tow.

We have live radio commentary of the rest of round three just starting up on BBC Radio 5 Live Sport Extra - or you can listen by clicking the link on this page.

There's also going to be a little quiz to keep you entertained. Bit of a tough one this evening... but no cheating please!

The PGA Championship has been held in 21 different US states - can you name them? Bonus points up for grabs if you can also name the courses and the winners.

Well, we do have about three hours left... #bbcgolf with your answers.