Peter Lawrie posted a closing round of 65 to take victory in the Challenge Tour Grand Final at Golf du Medoc near Bordeaux.
The 28-year-old Dubliner finished on 12-under-par 272, four strokes ahead of Julien Van Hauwe from France and eight clear of three players, including England's David Dixon and Simon Wakefield.
On a day that started with persistent rain that gradually turned to sunshine, Lawrie began a shot ahead and opened with six successive pars then reeled off six birdies in the next eight holes.
"I'm absolutely delighted and it's a great way to end the season," said Lawrie. "I said before I teed off that if I could just hit the fairways and the greens I had a chance especially how the weather was at the start.
"And I did just that. I never felt under pressure and that round has been coming for a long time."
Lawrie, who had already secured his European Tour card for next season, collected Stg£21,511 to climb to fourth on the Challenge Tour ranking, while Wakefield finished ninth after closing with 72 for 280.
The Staffordshire player got to six under after eight holes but was unable to make further inroads despite carving out a string of chances. He would have finished third on his own but he missed the final green to drop a vital shot.
Somerset player Dixon, who had to win to book a European Tour card, wrecked his chances with a double-bogey six at the fourth where he took four putts. He battled bravely and four birdies in six holes around the turn got him to five under.
But again his hopes slipped away, two bogeys dropping him back and even a final birdie at 18 could not hide his disappointment with a 71.
"I battled with the putter all day," he said. "The four putt at the fourth was the end of my round and it was just one of those days."