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'Astounding' McIlroy birdies six of last seven to hold record Masters lead
Sharing the overnight lead with Sam Burns, Northern Ireland's McIlroy made a hat-trick of birdies from the second hole to open up a three-shot advantage before bogeys at the fifth and 10th gave the chasing pack renewed hope.
But the world number two surged clear of the field down Augusta National's iconic closing stretch. Birdies on six of his last seven holes, including a sensational chip-in on the 17th, took him to 12 under par.
The seven under par round opened a huge lead over Americans Burns and Patrick Reed, with Ryder Cup team-mates Justin Rose, Tommy Fleetwood and Shane Lowry a shot further back.
"I've built up a nice cushion at this point. I guess my mindset is just trying to keep playing well and keeping my foot on the gas," said the 36-year-old, who will head out alongside Burns in the final pairing at 19:50 BST on Saturday.
"There are so many different ways to skin a cat. I've shot 12 under par for the first two rounds here. I've played well, I've hit good shots, but it hasn't all been amazing.
"I've relied on my short game when I've needed it, and I've certainly hit enough good wedges into those par fives to build the score that I have."
Magical 90 minutes tightens McIlroy's grip on the Masters
No plans to merely 'protect lead'McIlroy, who is hoping to become just the fourth player after Jack Nicklaus, Nick Faldo and Tiger Woods to win back-to-back Masters titles has held a six-shot lead at this point in a major before.
He went on to win the 2011 US Open by eight shots - claiming the first of his five majors - and also spreadeagled the field with an eight-shot victory at the 2012 US PGA Championship.
And he plans to maintain an aggressive approach around Augusta National over the weekend as he bids to match Faldo, Phil Mickelson and Lee Trevino's haul of six majors.
"Don't protect it. Go out and play freely, keep swinging," he said when asked what advice his 2011 self would have for him before Saturday.
McIlroy led that year's Masters by four shots going into the final round, but carded an eight-over-par 80 to tumble down the leaderboard.
"A big part of the lesson from the 2011 Masters to the 2011 US Open was don't get protective," he added. "Go out there and keep playing, keep trying to make birdies, stay as trusting and as committed as possible."
McIlroy also said he plans to watch tennis and spend time with his daughter Poppy to take his mind off the third round.
"That distraction is usually a good thing for me, especially with a late tee time and the lead," he explained.
"There are two really good semi-finals at Monte Carlo in the tennis. So I'll watch those.
"We've been watching the tennis early in the mornings. And then hopefully spend some time with Poppy. I think we're about halfway through Zootopia 2."
McIlroy has credited his fast start to the tournament with spending a huge amount of time practising on the course in the three weeks he took off from playing PGA Tour events after the Players Championship in March.
"I just don't like the three tournaments leading up to this event," said McIlroy, who has a home in nearby Florida.
"I'd rather come here. I did a couple of days where I dropped Poppy to school, flew up here, played, landed back home and had dinner with Poppy and [wife] Erica.
"I felt it was a better use of my time than going to Houston or San Antonio. It wasn't really about conserving energy, but just I felt the more time I could spend up here, the better.
"I've been on this golf course so much the past three weeks. That has been a combination of practice and chipping and putting around greens, and then just playing one ball and shooting scores and ending up in weird places that you maybe never find yourself and just trying to figure it out. I think just spending so much time up here has been a big part of it."
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McIlroy speaks to BBC Sport NI's Stephen Watson after breaking record
With no rain forecast over the weekend, Augusta's famously undulating greens are expected to become increasingly fiery as the tournament nears its conclusion.
With that in mind, McIlroy - who missed six fairways and five greens on Friday - is under no illusion about the scale of the task as he alluded to his previous Masters struggles.
"There's still a lot of work to do," he stressed to BBC NI.
"I've put myself in the best position possible going into the weekend but I know more than probably anyone else what this golf course can do to you.
"I need to keep my wits about me and play the weekend like I played the past two days."
