Zalatoris can't escape the trees properly so is playing three out of the rough when he plucks a wonderful shot out of the bag to stick it to 10 feet.

That putter though...it wobbles down tamely and doesn't drop so he cards another bogey.

In what has been a big difference between the two today, Pereira converts his par putt, albeit from a bit closer in, but he holds his nerve to extend his lead.

Justin Thomas comes up short and right at the par-four 17th. Bubba Watson must have some sort of sand-finding mission today and will play his second out of the left bunker.

Both play decent second shots, with crisp contacts. Birdie chances coming.

Rory McIlroy has had two pars on the 18th so far this week. He needs a birdie today.

Tee shot puts him in prime position, pinged straight down the middle.

Big chance gone for Rory McIlroy who can't make the birdie putt. He went chasing an eagle and ended up with par.

Abraham Ancer rolls his putt straight into the middle of the hole and he's moving up to within four of the lead.

Justin Thomas looks pumped.

That was only for par but the American who has dropped shots in two of his last four holes will hope to use that 24-footer as his inspiration to stay in touch over his final two holes.

That's going to sting for Bubba Watson mind. He was runner up at at Whistling Straits 12 years ago but his challenge here suffers a huge blow as he lips out from four feet.

A rare glimpse of Rory McIlroy's playing partner Abraham Ancer. The Mexican is chipping from off the back of the 17th green with his second shot. I'd give that 7/10. Pulls up about 10 feet short.

Rory from the sand. Flicks out but gets very little run, the ball failing to get over a little rise in the green and drifts maybe 25 feet away. 4/10.

Cool as you like. Matt Fitzpatrick goes to five under as he sweeps in his birdie putt. The Englishman sits three off the leader in a tie for third.

Huge slice off the tee from Zalatoris - not for the first time today...

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Rory McIlroy takes on the challenge of driving the 296-yard par-four 17th. The punters are screaming their encouragement, but he doesn't give his effort enough of a whack.

His ball plunges into the bunker protecting the front of the green. You feel he needs at least one birdie in his closing two holes to give himself half a chance on Sunday.

There aren't too many lucky breaks being handed out by Southern Hills today so you really do need to take advantage, but Pereira can't as he misses his birdie putt.

Zalatoris taps in for par eventually but that short, jumpy, stabbing action he has on those short ones really does make you nervous!

Matt Fitzpatrick almost drives the 17th but instead finds himself tucked up in the sand trap greenside.

Couple of big shots coming up. His first of those, scoots past by about 10 feet. Birdie chance still in the offing.

The leading pair both get onto the 15th green safely, but Zalatoris is in a different postcode to Pereira - who got a little bit lucky when just jamming his approach a touch right only to get a nice helpful bounce back down towards the hole.

A huge slice from Bubba Watson on the 15th leaves the American in the rough and his next shot hampered by a huge tree smack bang in the line of where he'd ideally like to play.

He shunts his next forward by 50 yards, giving himself a huge battle to save par. Can he get his chip on close? Nope. Bogey for Bubba and Justin Thomas, who made a right mess of his second and third.

Rory McIlroy is going birdie hunting again on the 16th. He's tamed the 523-yard hole with two arrow-straight shots, the second finding the green, 25 feet from the hole.

How's the putter feeling Rors?

White hot is the answer. The ball races into the hole at some pace. Those three dropped shots on the 11th are erased and he's back under par.

A driveable par-four coming up...

Matt Fitzpatrick misses the green on the 16th but that's no major problem.

The 27-year-old who last won at the Andalucia Masters, takes his putter trickles his ball down inches from the cup from nearly 50 feet away. Par saved.

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Another birdie for Pereira as he makes no mistake to take advantage of that brave tee shot.

And brave is the word as he's shown great character to get back into this after his bogey run - especially considering the situation.

Zalatoris scrambles for a nice par to keep his challenge going.

Cameron Young is about to set what could be a challenging clubhouse lead given the way everyone seems to be dropping shots today.

The 25-year-old American, who hails from Scarborough, New York, is making his US PGA Championship debut this week and has shot up the leaderboard in round three.

He's drilled his second to the par-four 18th into the centre of the green. Outside birdie chance.

He give his ball a wallop up the hill and it comes to rest six inches from the hole. Par finish to a terrific round of golf.

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Bubba Watson has been phenomenal out of greenside bunkers today. Bar the 10th, he's got himself out of jail on three or four occasions and he repeats the trick over on the 14th, to save his par with a putt from less than two feet.

JT's par is more straightforward, trickling his first putt down from the right fringe to tap in.

No holding back on the latest par three, and Zalatoris is unlucky that his drilled five iron takes a bad hop right and falls into the bunker - it looked the perfect hit.

Pereira has no intention of playing safe in response, and he muscles his tee shot right at the flag, and his ball just tiptoes over the bunker and ends up seven feet away.

A heavy sigh from Rory McIlroy tells you all you need to know about his birdie putt on the par-four 15th.

He's pulled his eight-footer to the left. A scratch of the nose and a disconsolate look. He knows that was a massive chance.