West Australian Min Woo Lee believes he is a step closer to a major championship breakthrough after finishing as the leading Aussie at the US PGA Championship at Valhalla Golf Club.

American Xander Schauffele had to birdie the 72nd hole to earn his own maiden major victory with a record score of 21-under par, edging Bryson DeChambeau (64) by a single stroke.

Tied with two-time major champion Collin Morikawa entering the final round, Schauffele holed a birdie putt from 27 feet at the first to take the outright lead.

He would never trail from that point on, yet had to navigate a treacherous final hole to better DeChambeau’s clubhouse mark of 20-under par.

His tee shot at the par-5 18th came so close to the fairway bunker that he was forced to play his second shot with both feet in the sand. An awkward 7-iron from 247 yards hooked into the fairway 36 yards short of the green, his subsequent pitch coming up six feet short of the hole.

As DeChambeau thundered driver swings on the practice range in preparation of a possible three-hole playoff, Schauffele stepped in and found enough of the left edge of the hole to make birdie and join the pantheon of major champions.

At 25 years of age, it is a place Lee wants to one day occupy and he left Valhalla feeling confident that he remains on the right path.

“Definitely trending in the right direction,” Lee told the PGA of America after a round of 4-under 67 that elevated him into a tie for 26th.

“I feel like I’m slowly becoming a better player.

“I left some out there but that’s just how it is. I think we can learn from that; solid week.”

A shot to just three feet at the first hole on Sunday set Lee up for a Sunday flurry.

He converted that birdie opportunity and a second from nine feet at the second to begin his final round in the best possible fashion.

There would be a dropped shot at the par-4 fifth but birdies at seven, nine and 10 had Lee 4-under on his round with eight holes to play.

He was unable to get up and down when he came up short of the green at the par-3 11th but got that back with a birdie from 17 feet at the 520-yard par-4 16th.

Thirteenth for the week in Strokes Gained: Putting, Lee was left to lament a 57% driving accuracy off the tee that restricted his birdie chances throughout the week.

“My driving wasn’t too good the last couple of days,” he admitted.

“If my driving’s up to scratch then I can definitely attack and make some more birdies. It didn’t feel comfortable the last two days so it was quite tough to make some birdies.

“I thought I did pretty good with my recovery the last few days, very happy.”

Tied for 16th through three rounds and chasing a first top-10 finish in a major, Lucas Herbert was on the back foot early with a double-bogey at the first, falling to a tie for 43rd with a closing 3-over 74 alongside fellow Aussie Jason Day (71).

Cameron Smith had six bogeys and four birdies in his round of 2-over 73 while Kiwi Ryan Fox shot 74 to finish 75th.

Photo: Michael Reaves/Getty Images

US PGA Championship Valhalla Golf Club, Louisville, Kentucky 1 Xander Schauffele 62-68-68-65—263 $US3.3m T26 Min Woo Lee 72-66-70-67—275 $113,962 T43 Jason Day 71-67-69-71—278 $48,969 T43 Lucas Herbert 69-67-68-74—278 $48,969 T63 Cameron Smith 68-70-70-73—281 $25,202 75 Ryan Fox (NZ) 72-68-72-74—286 $22,350 MC Adam Scott 72-73—145 MC Cam Davis 78-71—149 MC Kazuma Kobori (NZ) 73-77—150