Stade Francais and France winger Christophe Dominici could miss the first of the autumn Test matches after spraining his right knee.
The 33-year-old picked up the injury during his side's 29-15 victory over Toulouse on Saturday night at the Stade de France and was forced to leave the pitch after 23 minutes.
Dominici underwent further medical examinations on Sunday which revealed he will be out of contention for up to three weeks.
He will miss out on Stade Francais' two European Cup matches against Ospreys on October 23 and Leicester on October 29.
France start their autumn campaign on November 5 against Australia before taking on Canada in Nantes, Tonga in Toulouse and South Africa at the Stade de France on November 26.
National coach Bernard Laporte will announce his squad for the Test matches on October 25 in Marcoussis.
First-choice hooker William Servat is already ruled out after suffering a serious neck injury which is expected to sideline him for three months.