Big-hitting Bryson DeChambeau has laid some demons to rest with a stunning back-nine birdie barrage to seize the first-round lead at the weather-hit Masters.

The start of the year's first major championship was delayed by more than two and a half hours before DeChambeau quickly made up for lost time with a brilliant seven-under-par 65.

The American holds a one-stroke lead over lurking fellow American and world No.1 Scottie Scheffler, with Cam Davis the leading Australian four shots off the pace after opening with a steely 69.

DeChambeau's blistering round comes four years after he was derided for his infamous boast that he played Augusta National as a par 67.

"Because I can reach all the par-5s in two, no problem," he said back then.

"If the conditions stay the way they are, that's what I feel like par is for me. That's not me being big-headed. I can hit it as far as I want to."

Yet the 2020 US Open champion had only matched his "par 67" once before in 13 rounds at Augusta since making those comments.

He tried to set the record straight after Thursday's masterclass.

"The comment was definitely misinterpreted," DeChambeau said.

"I said it and I respect people's opinions on it. I have a level of respect for this golf course that's a little bit different than a couple of years ago.

"Clearly today was a great test of golf, and I was able to conquer a very difficult golf course today.

"Regarding the 67 comment, you mess up. I'm not a perfect person. Everybody messes up. You learn from your mistakes, and that was definitely one."

Scheffler, with two wins and a second from his past three starts, lived up to his pre-tournament favouritism with a bogey-free 66.

"Mission accomplished for today," Scheffler said.

"I did a good job of staying patient. We kept the golf course in front of us and I executed some really nice up-and-downs to keep the round going."

Exciting young Dane Nicolai Hojgaard is equal third with Max Homa after both returned early Friday morning to complete rounds of 67.

England's 2016 champion Danny Willett (68) is outright third playing in his first tournament in six months following shoulder surgery.

Davis is sharing sixth with Kiwi Ryan Fox at three under.

Top Australian hope Cameron Smith was happy to notch a one-under 71 after almost a week battling food poisoning.

Defending champion Jon Rahm opened with a disappointing one-over 73.

Rory McIlroy, in his ongoing quest to complete a rare career grand slam, made his best Masters start since 2018 with a 71.

Earlier, six-time champion Jack Nicklaus, with his wife Barbara on the bag, joined three-time winner Gary Player and dual champ Tom Watson as thousands of patrons surrounded the first tee to watch them hit the traditional opening shots.

"It's not so easy to put the ball on the tee now, is it?" Player asked the others, before striping one down the fairway.

"Watch out on the left and right," Nicklaus joked before he, too, drove it right down the middle.

It's the sixth consecutive year the weather has delayed at least some portion of the Masters.

There are 13 players from LIV Golf in the field this year, including defending champion Rahm, who left the PGA Tour on a half-billion-dollar deal late last year.

Australia's LIV Golf chief Greg Norman was again in the crowd, starting out early watching Rahm.

Norman said he was back at Augusta watching his LIV charges, and no doubt would have been thrilled with DeChambeau's surge.