Jordan Spieth picked up right where he left off at Augusta National 12 months ago, on top of the Masters leaderboard on Thursday night, but this time with Irish duo Shane Lowry and Rory McIlroy hot on his heels, writes Simon Lewis.
Last year's wire-to-wire winner Spieth shot an opening-round 66, six under par, to lead the Masters for a fifth successive round as his mastery of Augusta National showed no signs of letting up.
He will take a two-shot lead into Friday's second round ahead of Lowry and New Zealand's Danny Lee, who shot 68s.
Three-under 69s left English trio Justin Rose, Paul Casey and Ian Poulter, Irish Open champion Soren Kjeldsen of Denmark and Spain's Sergio Garcia in a tie for fourth with McIlroy a shot further back having bogeyed the last for a two-under 70 on an encouraging opening day for European hopes of a first Masters victory since Jose Maria Olazabal's second Green Jacket in 1999.
American Spieth, though, is the one they have to catch. It was the lowest round by a defending champion since Olazabal's 66 in 1995.
The Spaniard finished tied for 14th, 10 shots behind winner Ben Crenshaw. Spieth does not look likely to do anything similar.
In nine competitive rounds at the Masters, Spieth has not shot worse than level par 72 and has barely put a foot wrong around here since his mid-round wobble on the last day of 2014.
That was when bogeys at the eighth and ninth holes derailed his bid for a debutant's victory and handed Bubba Watson his second win in three years.
That was then, however. Last night Spieth was bogey free and in full control of his game on a windy day playing partner Paul Casey described as: “One of the toughest I've ever seen around Augusta National.”
“That was a flawless round of golf,” Casey said of Spieth.
“When he got into trouble, and you can ask him, looked like he didn't commit to his tee shot on 16, or wasn't happy, wind picked up, something happened. But he bailed out in the right place and what could have been an error, he turned into a wonderful par save. It was absolutely flawless.”
Spieth's assessment was more low-key, the Texan speaking as if he considered himself lucky to have signed for a 66.
“I would have signed for two under today and not even played the round, knowing the conditions that were coming up,” he said.
“Got a lot out of the round with what I felt like was kind of average-ish ball-striking. Just scored the ball extremely well, which is something I've been struggling with this season.
“I feel like my game's been trending in the right direction, I just haven't gotten scores out of how I felt I'd been playing. That normally just comes down to putting.
"Certainly made a lot of putts today. If I can kind of straighten things out with the iron play, hopefully we'll be in business. But, yeah, I am extremely pleased with that round today. I felt like we stole a few.”
Spieth, though, will have been left under no illusions about the size of the challenge facing him to become only the fourth player to successfully defend his Masters title and the first since Tiger Woods in 2002.
With the cream rising to the top early, Lowry and Lee were leading a large gathering of contenders who look set to begin the second round in hot pursuit, suggesting defending champion Spieth will have to continue working extremely hard and playing wonderfully well to stay ahead of the pack.
World number one Day will not be among Spieth's nearest rivals when play resumes on Friday, the Australian falling away dramatically with five dropped shots in three holes on the back nine.
Lowry made a fast start to only his second Masters appearance.
He had missed the cut on his debut but quickly made amends with four birdies in a row from the second hole to the fifth, adding another at the par-five eighth to reach five under, one off Spieth's lead just as Day dropped to four under with a bogey at the 10th although he rejoined Lowry with a birdie at 13.
The Irishman's first blip of the day came shortly after, when he overshot the par-three 12th green and bunkered, but Day followed suit, dropping a shot at the 15th.
Day did not stay the course, the pre-tournament favourite's round collapsing with a triple bogey six at the 16th having found water left of the green. He finished level par.
World number three McIlroy came into the Masters feeling his season was ready for lift-off and vowing not to repeat his slow start of 2015, when he surrendered 12 shots to Spieth over the first two rounds and never got close to winning the Masters title he needs to complete the career grand slam of majors.
The four-time major champion recorded his best Masters finish yet, fourth, but was left with feelings of what might have been that he was determined not to repeat.
A birdie at the second allayed such fears but they failed to spark a strong front nine and a bogey came at the par-three fourth.
McIlroy returned to one under with a seven-foot birdie putt at the par-four seventh and then improved by another shot with a six-foot birdie putt at the ninth, his putting not betraying the putting woes that have undermined brilliant performances from tee to green.
He gave the shot back at the 11th, only to move into the mix with an eagle at the par-five 13th, draining a 17-foot putt, and then sinking a 10-footer for birdie at 15.
There was a dropped shot at the 16th and he found a greenside bunker at 18, splashed out to leave a long par putt and had to settle for a frustrating bogey.
Fellow Irishman Graeme McDowell moved from one over par at the 12th to one under after 15, only to also bogey the last for a level-par 72.
Four bogeys for Darren Clarke between the ninth and 13th took the shine off an otherwise encouraging round for Europe's Ryder Cup captain in the last Masters appearance of his five-year exemption as 2011 Open champion.
He rallied with birdies at 14 and 16, where he sank a 14-foot putt, but bogeyed the last for a three-over 75, the same score as two-time champion Bubba Watson.