Monaco, the No. 5 seed, downed Frenchman Josselin Ouanna 6-3, 6-2.
France's Julien Benneteau beat Spaniard Alberto Martin 7-6 (7-1), 6-1 and Florent Serra of France eliminated Belgian Christophe Roche 6-3, 6-3 in other opening matches.
Jo-Wilfried Tsonga of France is the event's No. 1 seed.
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