Gloucester will be without Andy Hazell for their back-to-back matches with Bourgoin after medical reports called for a three week lay off.
The England international limped out of Gloucester's EDF Energy Cup victory over the Dragons on Friday and scans revealed knee ligament damage.
He will now not feature until after Christmas, meaning he will certainly miss Gloucester's Pool 2 double dates with Bourgoin and potentially the Guinness Premiership derby against Bristol the following week.
"We have developed a squad so we can cope with injuries to key individuals like Andy," said head coach Dean Ryan. "With the very nature of how Andy plays the game, he will pick up injuries from time to time and we have to manage that.
"It is obviously a blow not to have a player of his energy in the squad for a couple of weeks but we have plenty of options available to us and now we need to concentrate on getting his injury right."
Hazell, who was named the South West rugby player of the year on Sunday night, has made six appearances in all competitions this season.
