Justin Rose placed a four-shot lead on Thursday, thanks to a new superb back that saw him finish at seven under.
Despite being double after seven holes, the Englishman gathered and hit an eagle on eight and seven birds between nine and 17 to close four shots in front of Brian Harman and Hideki Matsuyama in second place.
The first round also saw a number of competitors ahead of the tournament.
“I knew that two to seven is not the end of the world, but I also knew that you were going in the wrong direction,” Rose, a two-time Masters runner-up, told reporters about her slow start.
“You can’t win the golf tournament today. Even with a 65, you can’t win it today. You can probably only lose it today.
“I haven’t pressed the panic button yet (after seven), but I reset just before that and I thought that if I could even return to equality, it would be a good day’s work.”
This is the fourth time Rose has led or co-led the Masters since the first round, a record she now shares with Jack Nicklaus.
The 40-year-old, who has played his first tournament since retiring from the Arnold Palmer Invitation last month with a back injury, was one of three players to finish under 70 alongside Harman and Matsuyama – quite contrast to last year’s tournament when 24 players recorded under-70 scores in favorable conditions since November.
Rose’s only previous major triumph came at the 2013 US Open; the closest he got to securing a green jacket at the Masters was in 2017, when he was beaten in a playoff by Sergio Garcia.
“I’ve played this course many, many times, it’s my 15th Masters, maybe, and the best right now is 67,” Rose said.
“I felt that today’s conditions are not the day to go and hit them and have the best there.
“It was quite windy – windy enough to be difficult – and obviously the green is incredibly firm and fast. The pine placements were correct, certainly not easy, but correct, and if you hit the right shot at the right time , you could take advantage “.
As for those below the standings, DeChambeau entered the Masters armed with a new driver and many expectations, but the great hitter got a series of shots from the counter in the first round.
His 76 included a double bogey on the fourth and bogeys on the fifth, eighth and 12th before his only bird at 15.
DeChambeau was joined by McIlroy at four, and the Northern Irishman finished in the top 10 at August National on six previous occasions, but never secured a green jacket.
Well positioned on a single sub, with three holes to play, Johnson defeated the 16th and defeated it in the 18th after his well came out of the hole.
2018 champion Patrick Reed finished the day tied for fourth in two under, while Justin Thomas and Jon Rahm – second and third in the world standings – finished one point and tied, respectively. .
CNN’s Ben Morse contributed to the reporting.