Briton Simon Dyson took advantage of a final hole error by Australia's Richard Green to clinch the Irish Open title on Sunday.
Dyson had posted a 15-under-par 269 total with a closing four-under 67 but Green's three-putt on the 18th green denied the lefthander a playoff, leaving him a stroke light after a 68.
Green had looked to have the advantage when he led Dyson by a stroke with two holes to go after birdieing the long 16th.
A stubborn Dyson refused to give in, though, and his birdie on 17 threw the two together again.
When Green then took three to get down from 50ft on the closing hole, the 350,000 dollars victory and a start in next week's WGC Bridgestone Invitational was the Englishman's.
His success followed a ninth place in his last event, the British Open, and his Royal St George's performance had driven him in Ireland, he said.
"After my finish in the Open it made me think, yes, I am a good player," Dyson told reporters. "I proved it to myself again today with a great finish."
Instead of now taking a week off, Dyson can now look forward to a visit to Akron as an extra reward. "I didn't play well there last year so I'm looking forward to doing better," he added.
Runner-up Green, who rattled his approach putt on 18 10ft past the cup and missed the one coming back, admitted that misreading his position coming to the last green cost him his chance.
"I thought I had a one-shot lead coming in the last hole and I think seeing Simon on 15 (under-par) added that bit of pressure on the first putt," said Green. "I hit it too hard."
Scotland's Stephen Gallacher holed a 30-footer for birdie on the last and captured third place on his own on 12-under 272 with a 68. Austrian rookie Bernd Wiesberger (66) was a further stroke back in fourth place.
The top two had shared the overnight lead with another Briton, former Ryder Cup player David Howell. Howell's absence from tournament contention for five years showed, however. A run of three back nine bogeys in four holes for a closing 73 finally ended his chances, dropping him to eighth place.
A disappointing week for Rory McIlroy concluded with a modest 71 for 281 in front of an equally disappointed gallery. The U.S. Open champion was outplayed by Italian rookie Lorenzo Gagli, who blazed to a 65 alongside him.
"It's been a frustrating week," said the 22-year-old Ulsterman after finishing tied 34th. "Being a home player you want to do well for the crowd and you push that little bit harder and sometimes that's not a good thing."
On his chances in the upcoming U.S. PGA Championship, he said: "I feel as long as I put the work in next week (at the WGC Bridgestone Invitational) and get my game ready for Atlanta, there's no reason why I can't have another shot at winning a major."
Last year's U.S. Open champion Graeme McDowell who was feted by similarly huge crowds all week, finished a stroke better than McIlroy with a 70 for 280.
Defending champion Ross Fisher could be forgiven if his mind was not completely on the job after his three-month old son Harry had been admitted to hospital overnight with a worrying rash and remained in care all day Sunday. A 73 dropped Fisher to a tie for 17th place.