It seems bizarre to say now given his dominant position, but there was a spell on Friday where you felt McIlroy was still not playing close to his best.
When McIlroy bogeyed the 10th, he dropped back alongside 2018 champion Reed on six under and his untidiness meant it was all to play for.
Some drives were being sprayed, some approaches were not as precise as they should have been.
At the end of his round, the statistics showed McIlroy ranked 90th in the 91-man field for accuracy off the tee.
Ultimately, it didn’t matter. His exceptional short game held his round together and when things did click into place on the tees and fairways, he motored through the back half in fabulous fashion.
After winning last year, there is not a melodrama every time he makes a bad shot. McIlroy has learned how to be patient around Augusta.
That seems to spell bad news for the rest of a leaderboard stacked with Green Jacket wearers, major title holders and Ryder Cup stars.
Staying even-tempered at the most famously punishing golf course in the world is a trait which two of the big names chasing McIlroy also recognise is necessary to succeed there.
Three-time runner-up Justin Rose, who is tied fourth, is targeting his own redemptive win after losing to McIlroy in last year’s sudden-death play-off and credits his own patience for his back-nine climb up the leaderboard on Friday.
“Early on things were tough out there. But I settled down and built the round back up,” said Rose, who is seven behind McIlroy after a three-under 69 on Friday.
“It’s a continuation of being on the leaderboard from last year and keeping the dream alive. I need to keep it as free as I can.”
Ireland’s Shane Lowry, who had a run of 14 successive pars, joined English pair – and victorious Ryder Cup team-mates – Rose and Tommy Fleetwood on five under par after two birdies in the final three holes.
“I was hitting good shots and just wasn’t converting but I was patient out there,” said Lowry, whose sole major win came at the 2023 Open.
But there is another contender, also from that European band of brothers, who has not yet learned how to stay calm at Augusta.
Tyrrell Hatton might have to learn quickly if he is going to push McIlroy.
The 30-year-old Englishman knocked in seven birdies on the way to a six-under par 66, seemingly carding the round of the day only to be matched by McIlroy.
“I definitely don’t stay calmer or more patient this week. If anything, I am probably more on edge,” said Hatton.
“I will just take each shot as it comes and see what we end up with.”