Rory McIlroy held a slender one-shot lead midway through the final round of the Dubai Duty Free Irish Open Hosted by the Rory Foundation, but Russell Knox was piling the pressure on the home favourite.
The Northern Irishman came into the final round with a three-shot lead over Masters Tournament champion Danny Willett after the duo finished the final three holes of their third round first thing on Sunday morning.
Knox was able to get finished on Saturday four shots behind the leader but he turned in 32 to close the gap on McIlroy, who is searching for a first win at his home Open.
The 27 year old has 12 wins on the European Tour - four of them Major Championships - but none in Ireland and had missed the cut the past three seasons at this event.
While Knox emerged as his main challenger, he was not the only man applying pressure with Willett turning with nine pars and Bradley Dredge and Jamie Donaldson also making major moves.
While the leading group opened with three pars - all missing good birdie chances on the second - Dredge was surging through the field as he birdied the second, third and fourth to join Willett in second and six under.
Knox's iron play had been exemplary on the first three holes and on the par five fourth he really made it count, putting his approach to 20 feet and rolling in the putt to leapfrog Willett into second place.
McIlroy maintained his three-shot lead, though, as he holed from eight feet for a birdie to become the first man this week to get to double-figures under par.
Another Knox birdie followed from 12 feet on the next and when McIlroy's second to the sixth found a horrible lie in the rough to the left of the green, a dropped shot opened the door for the WGC - HSBC Champions winner.
He three-putted the same green to let McIlroy off the hook but then took a very brave line on the par three eighth for a birdie to cut the gap to one.
Donaldson had birdied the first and fourth and when he rolled in another on the tenth, he joined the group at six under with Dredge making a gain on the same hole in the group behind to get to seven under.
A heavy hail storm then brought a delay at 1.06pm with the final group on the ninth fairway, and when play resumed an hour and nine minutes later all three players made par with Willett and Knox holing impressive putts.
Martin Kaymer had two eagles and two birdies in his round to get to five under but had just three holes left to play, with Sébastien Gros, Li Haotong, James Morrison and Matthew Southgate also four shots back.
