McIlroy led by two late, but bogeyed two of the final three holes to fall back into a share of the lead with Alvaro Quiros at seven-under 133. Both McIlroy and Quiros shot a one-under 69 on Friday at Hong Kong Golf Club and will be paired together for Saturday's third round.
While McIlroy is looking for his fifth straight top-five finish, Quiros is trying to bounce back after a year-end swoon. Quiros hasn't placed in the top 10 of an event since the Volvo World Match Play Championship, a span of 11 events.
"The most important thing is this afternoon, people are going to shoot low, but anyway, I'm going to be up there," Quiros said before McIlroy caught him.
Panupol Pittayarat (65) and Richie Ramsay (66) share third at six-under 134 and will be in the second-to-last grouping, while Miguel Angel Jimenez (70), Pariya Junhasavasdikul (65) and Danny Lee (65) are fifth at minus-five.
McIlroy seemed to be taking control after Quiros took the clubhouse lead in the morning wave, but faltered down the stretch.
"I didn't hit it quite as good. I hit it in the rough a lot, and that reflected in my score," McIlroy said. "It was pretty disappointing to drop two (strokes) in the last three (holes)."
He began with a birdie at the third to match Quiros for the first time at minus-seven, but bogeyed the next hole to fall behind. Toward the middle of the round, he surged ahead.
McIlroy had birdies at the eighth, 10th and 12th to move to nine-under, two clear of the field. He was looking good until the end, when bogeys at the 16th and 18th cost him sole possession of the lead.
"I still shot under par, and it's not all bad. I'm tied for the lead, and I've got a great chance to win over the weekend," McIlroy said.
Quiros experienced similar troubles down the stretch after starting strong.
He began on the back nine and had three birdies in a flawless display to make the turn at nine-under. On the front nine, however, Quiros was less than stellar.
Quiros bogeyed No. 1 to fall back to eight-under, and another bogey at the fifth dropped him to minus-seven. He bounced back with a birdie at the sixth, but ended his round with a bogey to end one shot better than where he started the day.
"Unfortunately, I didn't play as well as yesterday," said Quiros, who shot a 64 on Thursday.
NOTES: Defending champion Ian Poulter (68) sits six strokes off the lead at one-under...The cut fell at two-over 142, with 66 players making it to the weekend...Some notables that missed the cut include Justin Rose, Matteo Manassero, Edoardo Molinari, Ross Fisher and Pablo Larrazabal.