McIlroy was back to his brilliant best as he posted a sparkling nine-under-par 63 on Thursday, the former world number one carding seven birdies and an eagle at Emirates Golf Club, the scene of his first European Tour title in 2009.
That gave him a two-shot overnight lead over former Ryder Cup team-mate Edoardo Molinari, with defending champion Stephen Gallacher one of five players a further shot adrift.
With Molinari among the early starters on Friday and scoring conditions again excellent, McIlroy may well have expected to find himself facing a deficit when he teed off again at 1225 local time (0825 GMT).
However, as he warmed up on the range, McIlroy would have been pleasantly surprised to see his name still on top of the leaderboard, one shot ahead of Molinari and Ireland's Damien McGrane.
After one birdie and one bogey on the front nine, Molinari had briefly drawn level with McIlroy thanks to an eagle on the par-five 10th, only to immediately drop a shot on the next.
Starting on the back nine, McGrane had got within one of McIlroy with birdies on the 10th and 14th before a bogey on the first, while a birdie on the fifth took him back to eight under.
European number one Henrik Stenson was two shots further back as he continued his recovery from a bad start to his opening round. The Swede was three over par after five holes on Thursday but eventually signed for a 70 and picked up four birdies in his first 10 holes today.