World number three Stanislas Wawrinka stormed back from a set down to beat German qualifier Mischa Zverev 4-6, 6-3, 6-3 and retain the men's title in Geneva on Saturday.
The top-seeded Swiss looked frustrated early on as Zverev, ranked 33, broke his serve and went on to take the first set.
In front of a partisan home crowd, Wawrinka jolted into life and raced to a 3-0 lead in the second, sending fizzing forehands across court and down the lines beyond Zverev to take the set.
Wawrinka, who won the French Open in 2015, dropped serve once in the final set but broke Zverev three times, securing the title with another ripping forehand for his first tournament win of the year as he prepares for another Roland Garros campaign.
The French Open gets underway on Sunday.
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