After starting the final round a shot behind Andy Sullivan, McIlroy carded eight birdies in the first 15 holes to surge into a two-shot lead with two holes to play, only to then find the water with an “horrendous” tee shot on the par-three 17th.
However, the four-time major winner holed from 30 feet to salvage a bogey and take a one-shot lead up the 18th, which proved just enough to secure his fourth win of an injury-hit year after Sullivan’s birdie attempt narrowly missed.
“It’s definitely the longest putt I’ve ever made for a bogey,” McIlroy said after a closing 66 saw him finish 21 under par at Jumeirah Golf Estates, one shot ahead of Sullivan, with South African Branden Grace a distant third on 15 under.
“I don’t think there’s been one that’s ever come at a better time, so definitely the best bogey of my career.
“On Thursday, it was a similar yardage and I was in between a five and a six iron. I tried to hit a six iron off the back foot and left it out to the right. I tried to do the exact same thing today, hit the exact same shot. It was 40 yards off line. It was just a horrendous golf shot.
“I guess if I had been tied playing the last, I would have backed myself with my length, but giving myself that one-shot cushion made a huge difference, and I was able to just hang on.
“I’ve played really good golf this week, 13 under par at the weekend. I couldn’t think of a better way to finish the season so I’m really happy going into the Christmas break and looking forward to what’s in store for 2016.”
McIlroy missed three tournaments this summer, including the defence of his Open title at St Andrews, due to an ankle injury suffered playing football with friends and needed an exemption to compete in the European Tour’s season finale after not playing enough events.
Nearest rival Danny Willett felt that gave McIlroy an unfair advantage but was unable to dislodge the four-time major winner from top spot in the money list. It was a position McIlroy held since finishing fourth in the Masters before winning the WGC-Cadillac Match Play in May.
Willett had to settle for a six-way tie for fourth on 13 under which included Italy’s Francesco Molinari, who recorded a hole-in-one on the sixth in a final round of 68.
“I guess if someone had said you’re going to finish fourth and see where that gets you, you might have taken it,” Willett said. “Unfortunately, we are going to come up shy by one on the Race to Dubai, but hopefully next year, we’re in a similar position and can try and change the story.”
McIlroy walked away with a total of €3m thanks to the winner’s cheque and his share of the €5.7m bonus pool, and although the 26-year-old remains third in the world rankings, he has closed to within 0.48 points of number one Jordan Spieth after ticking off just one of the golf-related goals he wrote on the back of a boarding pass in January.
“Obviously I wanted to win majors, I wanted to improve in certain areas of my game and didn’t quite do that, but these things happen. You have to set yourself these lofty goals to try and get better.”
Sullivan held a one-shot lead overnight and extended it to three with birdies on the first and second, but looked to have run out of steam on the back nine until McIlroy threw the event wide open once more on the 17th.
“I thought, ‘I’m back in it’,” said Sullivan, who was roared on all week by 30 members of his golf club from Nuneaton. “But I gave him a great read on my (birdie) putt. I turned to my caddie and said, ‘I expect him to hole this’. That’s just the world-class performer he is.
“It was an awesome day. Just to come up head-to-head with someone of Rory’s quality, it was absolutely awesome and something that will stick with me for a long time going forward.”
Sullivan, 29, was ranked 150th in the world at the end of 2014 but won twice in South Africa and led from start to finish in the Portugal Masters last month to climb into the top 40. Staying inside the top 50 at the end of the year will secure a Masters debut next April.
“It’s going to be amazing. It will be a nice way to finish the season off to get an invite to the Masters.”
Shane Lowry finished in a tie for 48th place on one under par, but ended the year fifth in the Race to Dubai to cap a successful year for the Offaly man after his win the WGC Bridgestone Invitational at Firestone last August.