Miguel Angel Jimenez, who captured last week's BMW International Open, held a one-shot lead heading into the final round but had a closing 72 to take second place at 14-under-par 270.
Donald returned to the European Tour this year in an attempt to earn a spot on the European Ryder Cup team. It took little time for the Englishman Donald to break into the win column at the Scandinavian Masters.
"I'm glad I made the decision to come over here and rejoin the European Tour," said Donald, who was a winner on the PGA Tour in 2002.
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