Rory McIlroy took firm control of the Omega Dubai Desert Classic despite opening the door for the field with an erratic inward nine holes on the third day at The Emirates.
The world No 1 stormed into a six-shot lead with five birdies over the first eight holes, but he managed just one more at the 17th coming in as he settled for a 66 and a 54-hole score of 20 under par.
McIlroy will head into the final round with a commanding four-stroke advantage over Morten Orum Madsen, while Lee Westwood is six shots off the pace after a battling 69.
McIlroy’s putter was red hot over the outward half, but a missed birdie opportunity from inside two feet at the 10th appeared to knock his confidence and he was forced into scrambling mode for much of the remainder of his round.
But he managed to keep a bogey off his card for the second day running, although he had to hole a lengthy putt on the final hole to avoid a blemish after dunking his second into the water short of the green.
The 25-year-old got into his stride immediately with a 25-foot putt for an opening birdie, and he added another at the third before holing from 20 feet at the fifth.
He converted another excellent approach to the seventh and rattled in another 20-footer at the next to equal his best ever front-nine score over the Majlis Course.
McIlroy needed only two more birdies over the back nine to equal Stephen Gallacher’s 54-hole record of 21 under set in 2013, but his putter mis-fired for the first time at the 10th and he then struggled to find the fairways.
Eight straight pars
The 2009 champion strung together eight consecutive pars before breaking the sequence with another 20-foot putt for birdie at the 17th, but he looked set to drop his first shot since his final hole of the first round when he miscued his second at the last.
But after pitching to 18 feet, McIlroy judged the par-saving putt to perfection to stay at 20 under and ensure a comfortable cushion over the challengers ahead of the final 18 holes.
Madsen was the biggest mover in the second round as he fired a best-of-the-week 63, and he continued to make great strides up the leaderboard with a flawless six-birdie 66 that earned him outright second.
The Dane cruised to the turn in 32 and birdied all three par-fives on the inward stretch to move to 16 under, two ahead of Westwood and three clear of Andy Sullivan, Bernd Wiesberger, Danny Willett and two-time defending champion Stephen Gallacher.
But Madsen is fully aware of the size of the task he faces on the final day if he is to upset the odds and overhaul the four-time major champion.
"Obviously, Rory's going to be tough to beat. He looks like he's playing pretty solidly out there, as well," said the world No 194. "I'm just going to go out tomorrow and see if I can play some of the same golf that I played today.
"I was nice and calm all the way and putted well and hit the ball solid. I wasn't really in any major trouble, so that was nice. I won't be too disappointed if I don't win. I'll be happy if I do what I set out to do and play pretty solidly."
Westwood birdied the second and third only to give both shots back at the ninth, but the Ryder Cup veteran gave himself an outside shot at the title with two closing birdies which earned him a place in Sunday’s final threeball alongside McIlroy and Madsen.
Sullivan, Gallacher, Willett and Wiesberger all fired two-under 70s, but Graeme McDowell failed to build on three birdies in the first six holes as he laboured to a 72 to slip eight shots behind his compatriot at the top of the leaderboard.
Watch how the final round action unfolds when live coverage resumes on Sunday at 8am on Sky Sports 4 - your home of golf