Amen Corner may have cruelled Australia's Masters hopes for another year, as Cam Davis clings to the dream of a final-round rally after coming unstuck on a dramatic moving day at Augusta National.

Davis posted a roller-coaster one-over-par 73 on Saturday that left him at two under for the tournament, in a tie for sixth and still in touch with third-round leader, American world No.1 Scottie Scheffler.

Cameron Smith remains at one under, in joint-ninth and also in the mix, six strokes off the pace after a labouring 72.

Davis rued a crushing 45-minute stretch that sent the Sydneysider spiralling from five under to one under after storming to within two shots of the lead.

Australia's big halfway hope leaked the four shots in the first four holes of a horror start to the back nine.

After surging up the leaderboard with three front-nine birdies, Davis staggered around the most treacherous pocket in world golf after one bad swing on the 10th.

He had to chip out from the trees after a wayward drive, then fired his approach over the back of the green before taking three more shots for a dreaded double-bogey six.

He compounded the error with a bogey on the 11th, then shaved the lip with a short birdie putt on 12 and dropped another shot after dunking his ball into Rae's Creek on No.13.

Suddenly Davis had tumbled back to one under, six shots adrift of the lead.

He steadied with a bounce-back birdie on the par-4 14th before finishing with four straight pars, including a brilliant up and down from the drop zone after again finding the water on 15.

"I hung in there quite well. It was playing tough, but I feel pretty proud walking away with one over after a few, it felt like, disasters while I was out there," Davis said.

"I'm giving it everything I've got. Today I wasn't laying up and I was giving it a good crack.

"Hopefully tomorrow we'll make the right decisions in the moments and come away with a round that's as good as we can make it."

Davis is sharing sixth spot with American Xander Schauffele and Denmark's Nicolai Hojgaard.

Smith couldn't buy a putt all day.

After collecting his only birdie on the third, the 2022 British Open champion reeled off 14 consecutive pars before closing out his frustrating round with a bogey on the last.

"I'm still in the golf tournament," Smith said.

"The way that the golf course is playing, I feel really confident with my ball striking - probably the best I've felt in a while.

"It's only one or two their way and one or two my way, and it's really close.

"Just got to keep grinding it out."

Adam Scott showed some resilience with a sub-par round of 70 to edge his way back to four over and a tie for 26th, 11 shots off the pace.

But Min Woo Lee (75) slumped to seven over and Jason Day (76) eight over to round out the Australian challenge.