The Omega Dubai Desert Classic was set for a dramatic finish with Rory McIlroy and Li Haotong inseparable heading into the back nine at Emirates Golf Club.
Chinese Li entered day four with a one-shot lead and turned in 34 but playing partner McIlroy went one better to join him at the summit on 21 under.
That left the contest intriguingly balanced but McIlroy would be considered the slight favourite having gone 15 under over the first three days on the back nine.
England's Tyrrell Hatton was then at 18 under after ten holes, a shot clear of Frenchman Alexander Levy and two ahead of a large group five off the lead.
A win for McIlroy would see him equal Ernie Els as a three-time winner of this event and also go level with Darren Clarke as the European Tour's most prolific Northern Irish winner with 14.
Li was looking for just his second win from his first 54-hole lead, while McIlroy was seeking a remakable eighth consecutive top ten here since his win in 2009.
Low scoring had been the theme all week and Richie Ramsay continued that trend, posting a 64 to set the very early clubhouse target at 16 under.
A Chris Hanson 65 and a Jason Scrivener 66 saw them join Ramsay in the clubhouse but that was highly unlikely to get the job done at the end of the day.
The leading duo both struggled on the first, with McIlroy doing well to save par from a nasty lie off the tee and Li finding sand twice to drop into a share of the lead.
They both parred the second and then took advantage of the par five third, and with Levy dropping a shot ahead on the fourth, the leading pair were four clear of the pack.
It was threatening to turn into a two-horse race but Levy made sure he could still have a say with a stunning approach to the sixth and a monster putt on the seventh.
It was unclear whether McIlroy and Li were aware of that move but they both reacted on the par three, Li holing from the front of the green and McIlroy putting his tee-shot to eight feet for a pair of birdies and a three-shot lead.
Hatton had birdied the second and third and when he hit a beautiful approach into the ninth to turn in 32, his hopes were still just about alive.
McIlroy and Li both found the waste area off the tee on the eighth but saved par and with Levy bogeying the ninth and Hatton birdieing the tenth, the closest challnegers swapped places.
Byeong-hun An and Henrik Stenson both signed of rounds of 68 to join the clubhouse lead, with Miguel Ángel Jiménez, Tommy Fleetwood, David Lipksy, Chris Paisley and Andy Sullivan all out on course at that mark.