Bristol Bears will be without full-back Charles Piutau and prop John Afoa until February after they picked up injuries in their defeat by Leicester.
Piutau, 28, suffered a knee ligament injury in Saturday's loss and will be out of action until late next month.
The New Zealand international also sustained a broken nose following a tackle by Jonny May.
Afoa, 36, damaged a rib in the 31-18 defeat but is expected to return in the middle of next month.