Eurosport - Lyon winger Michel Bastos (AFP)
Brazilian Bastos was on his way back to fitness after having been out of action since September 16, but he relapsed.
"He had a problem last week and he is now unavailable for 10 days," coach Remi Garde was quoted as saying by L'Equipe.
Bastos, who was widely expected to leave Lyon in the summer, has scored three goals in four Ligue 1 matches this season and has become a key player for Les Gones.
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