The Northern Irishman carded a 67 on day three over the Earth Course to get to 14 under and put himself in pole position to claim a first Rolex Series victory and become the only player to win the Race to Dubai season finale three times.
Race to Dubai Rankings in Partnership with Rolex leader Collin Morikawa carded a 69 to sit at 11 under and was safely on track to become the first American to win the Harry Vardon Trophy as Europe's Number One.
McIlroy won this event in 2012 and 2015 and another win would not only take his tally of European Tour victories to 15 but also add a Rolex Series triumph to his four Major Championship and three WGC titles.
The 32-year-old's last European Tour victory was at the 2019 WGC-HSBC Champions but he has won twice on the PGA Tour this season - including last month when he beat Morikawa by one shot at the CJ Cup @ SUMMIT - to move back inside the top ten on the Official World Golf Ranking.
"I'm right where I want to be," he said. "I want to be contending on Sundays in golf tournaments and feel like I'm back to playing the way I should and the way that will get me back contending. I'm excited. I'm excited to go out there and try to pick up another one.
"After the bogey on one, responded well with birdies on two and three, ended up turning at three under par and then back nine was good. I got off to a really nice start on the back nine. I gave myself a good chance on 14 and 16 and didn't convert those. Then bogey on 17, which in the end was a good bogey.
"I just thought it was important to make birdie at the last to get into the final group as well. I knew that putt was to get into the final group and I wanted to do that, so it was a nice way to finish."
A poor tee shot led to that bogey on the first but he hit back with two putts on the par five second, an approach to four feet on the third and a 12 foot double breaker on the sixth to move into a share of the lead.
I'm back to playing the way I should and the way that will get me back contending. I'm excited. I'm excited to go out there and try to pick up another one
He found a bunker off the tee at the ninth but hit a sensational second to 13 feet to stay in a share of top spot at the turn before he stuck an approach to nine feet at 11th to take the solo lead.
After doing well to save par at the next, he put a tee shot to 14 feet at the par three 13th and a sixth birdie of the day handed him a two shot lead.
Joint overnight leader Horsfield had made a two putt birdie on the second but broke a run of nine pars with a bogey after missing the green at the 12th.
A 60 footer at the 14th for eagle then started a brilliant run as he holed from 23 feet at the next and put a stunning second to six feet at the 16th to share the lead.
McIlroy failed to make a remarkable save at the par three 17th after being fortunate to find the rocks off the tee but hit back with an up-and-down on the par five last and with Horsfield bogeying the 18th after finding sand off the tee, there was a two shot swing.
After going birdie bogey on the second and third, MacIntyre holed a remarkable putt from 72 feet on the fourth and a 20 footer with a huge right to left break for an eagle on the seventh before bogeying the ninth.
He then hit two smart approaches into the tenth and 11th, holed from 20 feet on the 12th and made a two putt birdie on the 14th before bogeying the last after finding the water in a 67.
Björk holed from 15 feet on the sixth and five feet on the eighth to turn in 34 before a 24 foot putt on the 12th edged him further up the leaderboard.
A birdie on the 14th was then sandwiched by a pair of dropped shots but a gain from six feet after laying up on the last saw him sign for a 69.
Morikawa holed a spectacular right to lefter on the sixth from 37 feet, adding to an approach to 11 feet at the first and a six footer at the second but closed his round with 12 straight pars.
"I'm still in it," he said. "Hopefully I can get off to a good start like I have been the previous few days and it's that middle stretch where I have not made any birdies. I have to take advantage of those tomorrow and hopefully keep the round going and at least hopefully start it on a good note."
Hansen carded a 68, two shots better than joint overnight leaders Catlin and Lowry, to sit a shot ahead of two time Major Championship winning German Martin Kaymer and two clear of England's Marcus Armitage, South African Dean Burmester and American Johannes Veerman.