Striker Moussa Dembele will reportedly miss Lyon's Europa League showdown with Rangers on Thursday.
French media say both he and team-mate Xherdan Shaqiri have been ruled out of the group stage opener at Ibrox.
RadioScoop claim former Celtic star Dembele - who has scored seven times against Rangers - has a muscle injury and will not travel to Scotland.
Shaqiri is being left behind as he "not completed his vaccination course."
In better news for Lyon boss Peter Bosz, three of his players have been granted quarantine exemptions by the Scottish Government.
Tino Kadewere, Lucas Paqueta and Bruno Guimaraes would all normally be required to isolate having been on international duty in red list countries last week.
But, after a request from the Ligue 1 side, all three will be allowed to play.
A Scottish Government spokesperson said: “After carefully considering the public health risk, we have agreed to allow the three Lyon players to travel to Scotland.
“International travel restrictions remain necessary to limit the importation of the virus and variants of concern. Red list countries pose the highest risk, which is why any exemptions have to be considered very carefully.”
