The 34-year-old, whose last European Tour victory was at the Czech Open in August 2010, finished on 14-under-par following a 3-under final round.
Scotland’s Richie Ramsay, winner of last week’s European Masters, and Spain’s Pablo Larrazabal were 12-under, with Scott Jamieson another shot back. Sweden’s Henrik Stenson, England’s Graeme Storm and Spain’s Gonzalo Fernandez-Castano were 9-under.
Larrazabal, Jamieson, Storm and Fernandez-Castano had all shared the lead after the third round.
Hanson collects a check for 300,000 euros ($384,500), the second-biggest prize of his career.
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