Brooks Koepka stumbled after a flying start to set up the prospect of a thrilling finish to the 105th US PGA Championship at Oak Hill.

Koepka took a one-shot lead over Corey Conners and Viktor Hovland into the final round, six weeks after enjoying double that advantage following 54 holes of the Masters.

The four-time major winner carded a closing 75 at Augusta National to finish second to Jon Rahm and felt he had “choked” under pressure, but looked set to exorcise those demons in style when he stormed out of the blocks on Sunday.

Koepka holed from four feet for birdie at both the second and third and completed the hat-trick from double the distance on the par-five fourth.

Hovland also birdied the fourth to remain three behind and picked up another shot on the next to close the gap after Koepka’s own attempt had caught the edge of the hole and stayed out.

Koepka showed a first sign of frailty with a pushed drive into Allen’s Creek on the difficult sixth hole, the resulting bogey allowing Hovland to get within a shot after he saved par from a greenside bunker.

Both players then bogeyed the seventh to bring several players back into contention, with Scottie Scheffler and Bryson DeChambeau both three off the lead.

World number one Rahm, commentating for CBS following a closing 71 which left him seven over par, had been full of praise for Koepka after his blistering start.

“He is a player that, when he gets in contention, is like a shark in the water,” Rahm said.

“He smells blood, especially on these types of courses. It suits his mentality of being even keel, plodding along and taking opportunities when they come.

“He came out aggressive and I don’t think people realise how dangerous some of these hole locations are. To be that precise (on the second) to give yourself three feet straight up the hill is incredible.”

Open champion Cameron Smith had recorded the lowest round of the week to date with a closing 65 and insisted no-one should be surprised that he and fellow LIV players were able to compete at the highest level.

“I gave up on that narrative about six months ago,” Smith said with a smile. “I think there’s been a few guys that have been trying to kick it along a little bit.

“We’re still out there. We haven’t forgot how to play golf. We’re all great golfers out there, and we know what we can do, and I think that’s what we’re trying to do.”

England’s Tyrrell Hatton was left to rue a nightmare opening round of 77 after subsequent scores of 68, 69 and 67 proved what was possible and left him on course to finish just outside the top 10.