Adam Scott has urged the United States Golf Association to refrain from dishing up a brutally difficult golf course at next week's US Open.

Speaking after finishing the US PGA Tour's Memorial tournament in Ohio, the world No.10 said the governing body of golf in America setting up US Open venues to be overly penal "doesn't set a good example" for the sport.

Scott was referring to the fact US Open venues are typically prepared with long, thick rough, narrow fairways and lightning-quick greens to prevent low scoring.

Four US Opens within the past 11 years have been won with a 72-hole total worse than par, including consecutive winning scores of five-over in 2006 (when Australian Geoff Ogilvy won) and 2007.

With this year's US Open starting on June 15 at new venue Erin Hills in Wisconsin, Scott implored the USGA to make the course "challenging and interesting".

"They've taken criticism for the last two years ... maybe it's time to do away with the even-par [72-hole] target," said Scott.

"Let's just have something that's a challenge and interesting, not just playing brutal.

"The ball is in their court. Hopefully they get it right this time, just from a playability standpoint.

"If their major pinnacle event requires courses to be the way they are, it doesn't set a good example."

In March, the USGA and golf's international governing body, the Royal & Ancient Golf Club, together proposed a series of rule changes in order to "modernise and make them easier to understand".

It followed the USGA coming under heavy fire for penalising American Dustin Johnson during his 2016 US Open victory.

Although Johnson won by three shots, the USGA was slammed for informing Johnson of the discretion mid-round before it had decided on the actual penalty.

"I think they've really dropped the ball with where the game is at over the last 20 years, and I know their intent is not to do that. I don't question their intent at all," said Scott.

"Their primary role of administering and looking after the game ... whether it's rule changes or any other decisions, I think their process is out."

American Jason Dufner kept the best for last, biding his time through a late lightning delay before sinking an almost 10-metre putt to win the Memorial tournament.

The monster effort for par was the longest putt Dufner had holed all tournament and it completed an epic comeback for the American, who earned a three-stroke victory at Muirfield Village in Dublin.

He carded 68 to finish at 13-under-par 275, becoming the second Ohio-born player to win the prestigious event, with the tournament's founder and host Jack Nicklaus the first.

Fellow American Rickie Fowler (70) and Indian Anirban Lahiri (65) tied for second on 10-under.

A day after shooting a miserable 77 to fall from a five-shot lead to four strokes behind on Saturday, Dufner roared back in the final round for his fifth PGA Tour victory at the age of 40.

Earlier, world No.3 Jason Day signed off in style with a two-under 70 and share of 15th, a career-best finish at his hometown event in Columbus, Ohio.

Queenslander Day had never finished inside the top-25 in eight previous starts at Muirfield Village, where he is a member.

Fellow Australian Marc Leishman (71) joined Day at five under the card, while Victorian youngster Brett Coletta bagged his first result on the US PGA Tour.

The 20-year-old Coletta signed for a solid two-under total off the back of his final-round 73 and finished in a share of 25th.

Scott was next best of the Australians, but a double-bogey, bogey finish ended with a disappointing 74 and the world No.10 dropped to one under, sharing 31st.

Perth's Greg Chalmers (72) finished at four over, Rod Pampling (70) at five over, Cameron Smith (77) at seven over, Curtis Luck (77) at 11 over and Matthew Griffin (82) at 18 over.

AAP