Christian Cevaer carded a second successive 64 to win the Finnish Masters by a shot from overnight leader Pehr Magnebrant of Sweden, who returned a 67.
The 30-year-old Frenchman finished on 20-under-par 268 after battling it out shot for shot with the 29-year-old Swede. But it all came down to an eagle three and a chip-in birdie, which saw Cevaer home.
Cevaer was still two behind Magnebrant playing the ninth, but he cut the deficit to one with a 50-foot putt for an eagle three; his opponent birdied.
Then Cevaer drew level at the par four 14th when he chipped in from 60 feet for his sixth birdie of the round. His seventh, at the long 16th, nosed him in front for the first time and even when he missed the final green with a three iron, he got up and down to save par and protect his lead.
Ireland's David Higggins and Peter Lawrie finished well down the field. Higgins added a 72 for a total of 283 while Lawrie shot 69 for 285.