Smith sits just one shot behind Korean leader Sungjae Im in solo second spot after a sparkling first-round four-under-par 68 at Augusta National.

Australia's World No.6 defied gusting winds to rattle off eight birdies in 16 holes in a round that could have been anything if not for two double-bogeys to start and finish.

But he was left only "a little disappointed" after finding a fairway bunker on the first hole, then missing a short bogey putt, and slicing his tee shot into the trees on the 18th and three-putting to blow a two-stroke lead.

"To be honest, those couple of double bogeys really didn't have too bad a shots in them. It's not like I was scratching it out of the trees," Smith said.

"Got my second shot into a reasonable spot and just misjudged the wind on both wedges. Just left myself in a bit of a tough spot.

"Other than that, it was just really solid."

RIGHT: Sungjae Im leads The Masters at five-under after round one. PHOTO: Jamie Squire/Getty Images.

Rain delayed Smith's round by half an hour, but nothing could stop the unflappable Queenslander from picking up from where he left off in winning last month's Players Championship in Florida.

The 2020 Masters runner-up hadn't played competitively since bagging a record 10 birdies in the final round at TPC Sawgrass to stamp himself among the favourites for golf's first major of the year.

Little has changed after Thursday's fireworks.

"Given the condition of the golf course and the condition with the wind and stuff like that, if you had have given me four-under at the start of the day, I would have taken it," Smith said.

"1 and 18 was obviously really frustrating. I think it'll motivate me the next few days."

With two wins already this year, Smith can claim golf's top ranking if he wins the Masters.

The 28-year-old attributes his rise to improved off-course discipline.

"The last five or six years I've been really inconsistent with my training, and probably the last eight months or so I've been just really consistent," Smith said.

"I've made lots of good changes, I think, to my body. I lost a little bit of weight and my body moves a little bit quicker when I don't have so much around my belly.

Min Woo Lee, alongside Marc Leishman, was the next best Aussie after a 73. PHOTO: David Cannon/Getty Images.

"I've definitely started to see my driver going probably a little bit further, definitely the swing speed up a little bit.

"The next step is just being able to control that and hit more fairways.

"(But) most of the time I feel pretty fresh walking off the golf course, which is a feeling I don't think I had for a long time, and it's I think why my game has probably got a lot more consistent through four rounds."

After opening with three birdies in a row, Im had his own missteps after making the turn in four-under.

"Given the condition of the golf course and the condition with the wind and stuff like that, if you had have given me four-under at the start of the day, I would have taken it." - Cam Smith.

The 2019 PGA Tour rookie of the year made back-to-back bogeys at 10 and 11 before getting both shots back with an eagle at the par-5 13th. Im then put another birdie on his card at the par-5 15th that has been lengthened and adjusted a little for this year’s tournament. His 67 Im’s fourth score in the 60s in seven rounds at Augusta, where he shot a 66 on the opening day in 2020 to eventually share runner-up honours with Smith behind Dustin Johnson.

Veteran Marc Leishman and Masters rookie Min Woo Lee are the next best Australians, six shots behind Im after rounds of one-over 73.

Fellow debutant Lucas Herbert and 2013 champion Adam Scott posted 74s and Cam Davis, also playing his maiden Masters, signed for a 75.

Tiger Woods signed for a one-under-par 71.