Once a perennial contender, Jason Day is making no bold promises as he continues his baby steps back to the top of golf in his first Masters appearance after two frustrating, at-times despairing years.

To many, including fans who watched the former world No.1 dazzle in a practice round with fellow Australians Min Woo Lee and Harrison Crowe at Augusta National on Monday, Day looks to be one of the leading contenders outside heavyweights Rory McIlroy, Jon Rahm and world No.1 and defending champion Scottie Scheffler.

In addition to a stellar record around Augusta, including a tie for second on debut and third in 2013 when Adam Scott won, Day boasts top-20 finishes in all seven of his PGA Tour events this year and is fresh off making the quarter-finals at the WGC-Dell Technologies Match Play.

But the 35-year-old refuses to talk about challenging for the green jacket, knowing he's still not where he needs to be after undergoing a swing overhaul with coach Chris Como to combat the back injury that threatened to end his career.

Noting, way too technically for the average golfer, how his elbows, hips, right arm, wrist and hands must all be in sync, Day confessed to still having too many thoughts during his swing process.

"If I can move it to the point where I could maybe have one or two swing thoughts, that would actually help a lot," he said.

"If you go and watch Rory on the range, or even play golf, even Tiger, these guys look like they are just free flowing everything. They can hit any shot.

"I'm kind of physically forced to have to think about this stuff out on the golf course because if I don't, then I go back into some bad habits, and that can potentially harm my back.

"So I'm forced to be able to have to think about this stuff. Really minute, small things that you don't really see to the naked eye.

"But things are moving in the right direction. The strike and the flight, the trajectory, the spin, the way it comes out, I'm starting to have a lot more control.

"The next step is being able to shape shots."

Until then, Day knows he's up against it competing in the extreme heat of battle at major championships with the tour's big three.

"Oh, they are playing some good golf," Day said.

"It's actually really exciting to see. I played against Scottie in the Match Play and I know that he's a good, solid putter, but if he was top 10 in putting, he'd dominate for a good, long while. He's got a really good head on his shoulders.

"Rory has been a very dominant force in the game of golf for a very long time, and Jon is such a solid player. His Top 10s to how many events he's played is unbelievable, the percentage.

"So to get back to that, I think it feels like a long way, but I know it's not that far.

"It's hard to be patient but just small little things happen along the way, and things get gradually better and better.

"Then all of the sudden you're back there. Last year I was 175th in the world, and I'm back to 35 in the world, which is nice."

In the long run, Day believes his new swing will be even more technically sound than when he dominated in 2015-16 with eight PGA Tour wins.

"With the current changes that I'm working on, hopefully that improves the ranking there," he said.

"And if I can kind of get back to my putting the way it was in 2015, 2016, that will definitely yield more wins for sure.

"I've just got to be patient with it."