A five-under 65 has lifted Australian Adam Scott to within two shots of the lead after the third round of the US PGA Championship on Sunday.

The 2013 Masters champion fired the lowest score of the day to jump to outright second at 10 under, two shots behind Brooks Koepka at Missouri’s Bellerive Country Club.

Scott was ranked No.1 for approach play, hitting 10 of 14 fairways and 15 greens in regulation.

He then backed it up on the greens by collecting six birdies to stay in touch with the leader.

The Queenslander, 38, will tee off in the final group on Monday morning AEST hoping to secure his second major.

He is one shot ahead of Jon Rahm (66), Rickie Fowler (69) and second-round leader Gary Woodland.

Jason Day needs his game to be sharp to be any chance of winning the US PGA Championship on Monday. Photo: Getty

Fellow Aussie Jason Day endured a frustrating third round of 67 but is still within four shots, sharing sixth with defending champion Justin Thomas (68) and Tiger Woods (66).

The 2015 champion Day said there was no secret to how he could climb the leaderboard when it counted most.

“If I can get out of my own way and just play, don’t think about anything else,” Day said.

“If it’s not going my way early, I can’t force things or get carried away.

“Everything will need to be sharp but if I have to pick one it will be driving and putting. I think there are low scores in me tomorrow.

“I don’t think someone’s going to run away with it tomorrow; it’s still a major championship.”

-with AAP