Norrman overturned a six-stroke deficit during a gripping final round, following six birdies in an eight-hole stretch by taking advantage of the par-five last to close a sensational bogey-free 65 and set the clubhouse target at 14 under.

The Swede was then made to wait for nearly 90 minutes as the chasing pack all faltered down the closing stretch, with Norrman finishing a shot clear of overnight leader Hurly Long and Shane Lowry sharing third spot with Grant Forrest, Thirston Lawrence and Ryan Fox.

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McIlroy held a share of the lead during a storm-affected Sunday, only to find the hazard four times in a final-round 74 - including twice in a triple-bogey at the 16th - to end the week in tied-16th.

How Norrman prevailed in Irish thriller

Long took a one-shot lead into the final day but lost his advantage with a three-putt bogey at the second, with the German in a share of the lead alongside McIlroy, Forrest and Min Woo Lee when play was suspended for over 90 minutes due to thunderstorms.

McIlroy birdied the first and scrambled from the sand to take advantage of the fourth but fell two behind when he found water and double-bogeyed the seventh, with Fox edging ahead when he followed back-to-back birdies from the fourth by adding another at the eighth.

Norrman opened with six pars and was outside the top-20 on the leaderboard until he began his move by birdieing the seventh and making three in a row from the ninth, with back-to-back gains from the 13th then pulling him level on 13 under.

Long responded to a bogey at the eighth by draining from 20 feet at the ninth, while Forrest birdied the tenth to briefly make it a four-way tie at the top again, only for Fox and Forrest to both slip back by dropping shots at the 12th.

Norrman two-putted at the par-five last to add a seventh birdie of the day and move to 14 under, which suddenly moved him into a two-shot lead when Long followed a birdie at the 12th by bogeying both his next two holes.

McIlroy was three back with five to play but saw his hopes ended on the penultimate hole, where he had to hole from 15 feet just to salvage a triple-bogey, with the Northern Irishman ending five strokes back despite a closing birdie.

Fox bogeyed the 17th to leave him requiring a final-hole eagle to force a play-off, only for him to have to lay up and leave a closing par, with the New Zealander matching the closing 70 from Forrest.

That left Long the only player who could catch Norrman, who saw his victory secured when the German - requiring an eagle at the last to get to 14 under - had to settle for a two-putt birdie to lift him to solo second.

Lawrence finished birdie-eagle to also join Lowry in a share of third, while Scotland's Connor Syme carded a bogey-free to sit as one of five players a further shot back in a share of seventh.

Norrman delighted by Irish success

Norrman's victory follows his breakthrough success at the Barbasol Championship earlier this season, with the win sending him into the world's top 100 for the first time in his career.

"It means everything," Normann said. "Obviously such a cool event to play. The fans have been incredible. I've really had a fun week. It's a long wait [as later starters finished] but yeah, super happy.

"The front nine was huge. I was playing so-so and then I birdied the seventh and ninth to get some momentum going into the back. I think that was key today. Obviously if you win, you're doing something good. It's a world-class event, and honestly I can't believe it's happened."

What's next?

The DP World Tour heads to England next for the BMW PGA Championship, where all 12 of Europe's Ryder Cup team are schedule to compete, with extended coverage from Wentworth throughout the week live on Sky Sports.

Lowry returns as defending champion, having held off McIlroy and Jon Rahm to win last year's contest, with live Featured Group coverage beginning on Thursday from 8.30am on Sky Sports Golf ahead of full coverage from midday.

Watch the Ryder Cup this month exclusively live Sky Sports. Live coverage of the opening day begins on Friday September 29 from 6am on Sky Sports Golf. Stream the PGA Tour, Ryder Cup and more with NOW.