A towering three-wood approach from 286 yards to the 18th hole at Jumeirah Golf Estates finished just five feet from the pin to set up a closing eagle and give McIlroy an eight-under-par 64, his lowest score in an event he won in 2012 and 2015.
That left the world number two just a shot off the lead held by France’s Mike Lorenzo-Vera, who shrugged off a lingering illness to cover the back nine in 30 with six birdies in the last eight holes.
Rahm and Fleetwood are among the five players who can end the week as European number one, but Austria’s Bernd Wiesberger maintained his place at the top of the projected Race to Dubai standings thanks to a battling 70.
McIlroy is without regular caddie Harry Diamond this week but feels so at home at the venue for the season-ending event that he feels he could play it “blindfolded” and such confidence was reflected in a flying start.
The 30-year-old Northern Irishman lipped out three times on the front nine but still recorded five birdies and recovered from his only bogey of the day on the 12th to birdie the 15th and 16th before conjuring up a picture-perfect finish.
“Honestly it’s possibly the best shot I’ve hit all year,” McIlroy told Sky Sports.
“The wind was off the left so it was a nice one for me to just aim straight at the pin and know that if I hit my little draw it should hold and I just flushed it.
“I carry my three-wood off the deck about 280 (yards) so it was right on the limit, but as soon as I hit it I knew it was perfect. It was right out of the middle. Great to finish like that, and yeah, it was a great round of golf.”
McIlroy has won four times this season and returned home from his latest success at the HSBC Champions in China to a surprise from his wife Erica in their new home in Florida.
“We had just moved into our new house a couple of months ago but we still had not moved everything in and the trophy cabinet hadn’t been built,” McIlroy explained.
“I got back from China, walked into our sort of game room and up on the wall were all the trophies and stuff. It’s a nice reminder sometimes. All that stuff had been in storage for a year and a half, so the first time I had seen the Claret Jug and US Open trophy and all that sort of stuff.
“It’s cool but it’s also a great motivator to think, you know, I’m still pretty early in my career and I’ve done quite a lot but I still want to do so much more.”
Fleetwood had made the ideal start by holing his approach to the first for an eagle two and there was a three-shot swing on the hole as playing partner Wiesberger three-putted for bogey.
Birdies on the second, seventh, eighth and 10th took Fleetwood to six under par, but he could only play the remaining eight holes in one over and was fortunate to see his drive on the 18th bounce off the rocks on the edge of a water hazard and back into the fairway.
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