The Norwegian who became World No.3 witth his win came from six shots back to force a sudden-death decider on Sunday before edging out Englishman Richard Bland on the first extra hole.

Queenslander Adam Scott also threatened the leaders briefly in the climax at the Emirates Golf Club but he faded to finish joint-ninth.

McIlroy had looked to have the tournament within his grasp, holding a share of the lead heading down the stretch with his closest rivals having all finished.

Yet, after scrambling a par following a poor tee shot at the 17th, he then found the water on the par-five 18th and suffered a costly dropped shot.

Rory McIlroy watches his ball disappear into the water fronting the 72nd green on Sunday. PHOTO: David Cannon/Getty Images.

The bogey meant he signed for a 71 and finished on 11-under, one behind Hovland and Bland, who went on to replay the 18th.

Hovland played it superbly and sealed victory with a two-foot birdie putt.

"This is pretty wild, I didn't really think this was possible going into today," Hovland told Sky Sports in an interview which, by chance, was conducted by Bland's coach, TV presenter Tim Barter.

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"I knew I had to shoot a real low number but a lot of things had to go my way. I'm thankful that it did.

"I'm pumping right now. It's a bit surreal."

"This is pretty wild, I didn't really think this was possible going into today." - Viktor Hovland.

The 24-year-old began his round way off the pace but, on a day of tension and drama, put himself among the contenders with four birdies on his front nine.

His hopes took a knock as he bogeyed the 15th but he then surged into a share of the lead on 11-under with stunning back-to-back efforts on his next two holes, holing a 35-foot birdie putt at the 16th and then eagling the par-four 17th after a brilliant tee shot onto the green.

This coincided with third-round leader Justin Harding all but seeing his hopes disappear with a triple-bogey at the 11th.

Hovland claimed another birdie on the last to record a 66 and set a clubhouse target of 12-under.

This was later matched by 48-year-old Bland, who – after three successive birdies around the turn – had put himself within striking distance and quietly kept himself in the picture.

Hovland and Bland, who is enjoying a late career renaissance after his victory at last year's British Masters, fought it out but the Englishman, despite an excellent chip on to the green in the play-off, was unable to match the Norwegian's birdie.

Scott had four birdies in the first 10 holes but a couple of bogeys on the home stretch ensured he ended with a three-under 69, finishing on seven under, five adrift of Hovland.

Compatriot Lucas Herbert was another couple of shots further back after a 70 left him in joint-18th, while Queensland's Maverick Antcliff had seven bogeys in his 78 to finish on five over.