Marcel Siem carded a final round four-under 67 to win the French Open at Le Golf National near Paris.
The German came home a shot clear of Italian Francesco Molinari who came out of the pack with a remarkable closing 64 which began with a double bogey at his opening hole.
Siem, winless on the European Tour since his sole victory at the 2004 Dunhill Championship, went out in 33 with birdies at three, six and nine and added two more at 14 and 15.
Two clear playing the 470-yard par four 18th, the 31-year-old drove into a bunker but, using his two-shot cushion, he laid up, wedged onto the green and then two-putted for a winning total of eight-under 276 and a first prize cheque of nearly £420,000.
"I'm so happy. It means a lot to me. So many tournaments I kind of destroyed already this year, I'm so happy I got it done in the end," said Siem who revealed he would celebrate with some French champagne rather then re-enact Thomas Levet's victory jump into the lake at 18 which resulted in the Frenchman breaking his leg 12 months ago.
"I was very nervous," said the pony-tailed German. "The last stretch is one of the toughest stretches we have on tour. I made great golf shots. I hit it very close on 15, made a good shot on 16 and on 17 I even hit the flag.
"I stayed very calm," said Siem, whose hot-headed attitude on the course has cost him in the past. "It means so much to me to win after that long stretch. It's all about winning in the end."
Siem's victory also gets him into The Open Championship at Lytham on Thursday week.
Frenchman Raphael Jacquelin took solo third on six-under after England's Ian Poulter and Sweden's Henrik Stenson suffered costly finishes.
Poulter ended bogey-bogey to slip back from seven-under to five-under while Stenson spiralled all the way back to four-under after finding water at the last and racking up a triple bogey.
Overnight leader David Howell tied fourth with fellow Englishman Poulter and David Lynn. Howell steadied the ship after two bogeys in his first three holes but was only able to find one birdie all day.
Lee Westwood, who hurt his right knee and groin before Saturday's third round 76, carded a one-under 70 for a five-over aggregate in his last tournament before The Open.