Early in the back nine Saturday the two-time US Open winner led by five but then, almost inexplicably, he dropped back to back shots at the 14th and 15th and it was suddenly game on again.
An unlikely save from 10 feet after missing the green at the par-3 16th restored order and a two-putt birdie at the par-5 17th sees him 12-under and taking a two-stroke advantage into the final round over Australia’s Adam Scott.
Jon Rahm, Rickie Fowler and Gary Woodland share third at 9-under with Jason Day one of six players at 8-under and T6, that group also including Tiger Woods and defending champion Justin Thomas. (A full wrap of the Australians at the PGA can be found here.)
But it is Koepka who is calling the shots after an impressive display Saturday, his 4-under 66 bettered only by Scott and the American showing few weaknesses as the day unfolded.
“I felt good,” he said after the round. “I’m putting really well and driving really well.
“l felt like I made those key putts to kind of keep the round going. The par save I made at 11 was kind of big. I felt like that could have been a turning point.
“Then I just didn’t put the ball in the fairway on the back side, which you have to do out here if you want to be able to score.”
Both back nine bogeys came after errant tee shots, Koepka clearly disappointed with the miscues but pleased to drop just one shot each at both 14 and 15.
“I hit it behind a tree (at 15, where he had to take an unplayable) and missed the fairway at 14,” he said.
“You’re in jail already and just trying got get out of there with best score possible.”
With 14 players within five shots of the lead, and eight of those major champions, tomorrow promises to be a shootout.
England's Matt Wallace had an ace at the par-3 16th
Scoring has been low all week and while Koepka is in command it’s unlikely a round of even par will be good enough.
Among the main dangers will be the two Australians in Scott and Day but Woods and Justin Thomas will also fancy their chances after a day where both missed several opportunities.
Woods is playing well enough to be a genuine threat tomorrow after a 4-under 66 but will feel he let some shots slip, particularly a golden opportunity at the par-5 17th where he three putted for par.
A majestic 4-iron to 23 feet set up the possibility of an eagle and while missing that was disappointing, sliding the four foot birdie effort past the right lip was excruciating.
“If you look at it, I left pretty much every single putt short on the back nine,” he said of the mis-step.
“The greens were getting fuzzy, they're getting slow, and I didn't hit the putts quite hard enough. And I made sure on 17 I did.
“And I blew it by about four feet and then pulled the next one.”
Thomas said he was happy to be done for the day and looking forward to being in the mix tomorrow though expects it to be a shootout.
“There's a lot of really, really good players that are up there, so I'm going to need to put together a pretty special round tomorrow,” he said.
“But I know I'm capable of doing it, it's just a matter of doing it.”
TIGER WOODS IS A GENUINE THREAT AT THE PGA:
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