We always knew that Justin Rose liked the Masters.
The 2013 US Open champion proved as much by losing a play-off at Augusta National in 2017, finishing tied second two years earlier and notching another three top 10s at the course.
We also knew that he had a habit of blossoming early in the week.
He claimed a solo first round lead in his second visit (2004) and shared the 18-hole lead in both 2005 and 2006. Moreover, no less than four times in the last six years he was tied sixth or better on Thursday evening.
He'd made only one top 15 since the start of last August, had to withdraw from his last start with a back spasm, and hadn't been seen on the course since the first week of March.
Another good Masters week was beyond him, right?
The 40-year-old opened the 2021 tournament with a 7-under-par 65, brilliant enough by its own account, but comparison with his peers on this early April day improved the performance whichever way you measured it.
Using traditional numbers, it was one of only three sub-70 rounds all day, and, judged by modern metrics, the effort was just the eighth time in Masters history that a player gained over 9.5 strokes on the field.
Even more remarkably, after seven holes, such a score seemed a ludicrous prospect: he'd made five pars and two bogeys and there was absolutely nothing to get excited about.
"But I didn't panic," he said afterwards. "I still knew this was not a day to play yourself out of the tournament. Okay, I didn't see 9-under through the last 11 holes coming. But it (was a consequence of) not panicking."
If that was one advantage of experience paying dividends, it was far from the only one.
"This spring, we're playing off the memory bank," he said. "It reminded me of years past today. You know, it was fun in November, better to be playing than not, but it was different and this week the course has teeth. You have to respect it so much more in spring."
He heads into Friday four shots clear of Brian Harman and Hideki Matsuyama with the quartet of Will Zalatoris, Webb Simpson, Christiaan Bezuidenhout and Patrick Reed five back after signing for 70s.
Rose revealed to the Daily Telegraph last week that he had played the course many times in recent week. "In my head," he added. "Sat in my trophy room, for inspiration, visualising each shot."
Those powers of visualisation may have further tests this week: he is the third golfer to hold a four shot 18-hole lead and the previous two failed to win.
In the 21st century round one leaders at Augusta National are only 3-for-28 at claiming a Green Jacket; solo leaders are just 1-for-15.
The Englishman himself has held one first round four shot lead, at the 2006 FUNAI Classic, and he finished tied sixth. He is 2-for-11 at converting wins from all solo advantages at this stage.
It's far from a done-deal and he is 7/2 to win with Bet365.
Lefty No. 4?
In the 21st century left-handers have thrived at Augusta.
Phil Mickelson has won three Green Jackets, Bubba Watson two and Mike Weir one.
Is it possible that Brian Harman can join their ranks? It seemed implausible at the start of the week because his course log book read MC-T44th, but his opening lap of 69 was a repeat of his final score in his last appearance in 2018.
You'd be surprised if he maintained his current rate of progress, but Augusta winners need hot putters and Harman had the second best Putting Average at January's The American Express and topped the category at THE PLAYERS last month.
He's 28/1 to win with SkyBet.
Here's a strange thing about Patrick Reed at the Masters: between his debut in 2014 and 2017 he never went sub-70, averaged 74.25 shots per lap of the course and didn't land a top 20.
Since then, he won the tournament in 2018, was T36th on defence, T10th last year and carded a 2-under 70 in round one. He's gone sub-70 in six of those 13 circuits and averages 69.85. That's nearly 18 shots better off per tournament.
In that second half of his Augusta career Reed is 3-for-3 at breaking par in round two and averages 67.00.
He's 12/1 to win with SkyBet.
Through eight holes of his first round Jordan Spieth was enjoying a decent round of golf, making birdies at the two front nine par-5s against a bogey at the fourth.
A winner last week, a three-time first round leader at Augusta, he seemed like the man most likely to challenge Rose for top spot.
Then, having thrashed at his tee shot from the ninth tee, his caddie pointed right and Spieth cried, "Oh my goodness."
The ball flailed right into trees and Spieth found it, but clattered his second blow flush into a trunk and the ball flew deeper into the woods. He located the fairway with his third, but the die was cast and a triple bogey-7 ensued.
His response? Birdie-3 at the 10th, eagle-3 at the 15th, seven pars elsewhere and a score of 1-under 71.
"I had the same nerves I always have at the Masters on the first tee," he said afterwards. "And definitely I turned it around on the back nine.
"I thought, 'If I can shoot 1-under on the back nine, I'm still in it and I managed 3-under.'
"I would have signed for 1-under ahead of today so that's okay."
The resilient Texan is 5-for-7 at going sub-par on Friday and far from out of it.
He's 7/1 to win with SkyBet.
Tyrrell can keep his Hatton
Tyrrell Hatton completed a 1-under-par 71 which surprised no-one more than the Englishman himself.
"This place has not been kind to me," he said. "It's not a course I feel comfortable on. Putting is a strength of mine, but I've not putted well here.
"I don't expect to be contending here although I want to give myself a chance. But if there is one major I'm least likely to do well in, based on my record and how I feel on the course, it would be this one.
"The green are pretty scary. They were the fastest I've putted on."
If you think those words sounds a little despondent, his record explains why.
His 71 was not only just a second sub-par lap in 13 efforts, it was also the first time he hasn't needed at least 73 shots on either Thursday or Friday.
Rock on Tommy
If Tommy Fleetwood maintains golfing protocol the bar bills must be proving quite expensive these days.
In his last start at the WGC Dell Match Play he helped seal a quarter-final berth with a hole-in-one against Dylan Frittelli and on Thursday he was at it again, taking dead aim at the pin on the par-3 16th.
It earned him a large crystal bowl and sharpened his scorecard too. He eventually signed for a 2-over-par 74.