Nicolas Mahut beat Alexander Zverev 7-6 7-6 to reach the second round of the Open 13.
Mahut, who next plays qualifier Norbert Gombos, withstood 10 aces from Zverev, seeded fifth and considered one of the rising stars of tennis. Both players dropped serve once in the second set.
Richard Gasquet, 6th seed, defeated Robin Haase 6-7 6-3 6-2, who had 14 aces but dropped serve five times. Gasquet next faces Mikhail Youzhny in the second round.
Julien Benneteau did not face a break point in a 7-5, 6-4 win against Denis Shapovalov, who had 16 aces but dropped serve twice. Benneteau next plays Gilles Simon, a two-time tournament winner.
There were also first round wins for Jan-Lennard Struff; Ajlaz Bedene, Illya Marchenko and Sergiy Stakhovsky.
Defending champion Nick Kyrgios, who is seeded third in Marseille, takes on Malek Jaziri in the second round on Wednesday.
