Lyon centre-back Jean-Alain Boumsong is a doubt for next week's Champions League opener against Fiorentina after picking up a groin injury in training today.

Boumsong suffered the knock in a collision with fellow defender Anthony Reveillere and was helped back to the dressing room by medical staff.

The 29-year-old former Rangers and Juventus defender had only just shaken off a similar problem and is expected to rest up for a few days while Lyon's medical team assess this latest setback.

"Jean-Alain feels a pain in the groin and will be rested for 48 hours," read a team statement.

"An update will be done with him Friday."

Boumsong faces a race against time to be fit for OL's Ligue 1 match against Lorient on Saturday and the Champions League Group E clash with Fiorentina at Stade de Gerland the following Wednesday.