Ulster back row Juarno Augustus will be sidelined “for a number of weeks” because of the ankle ligament injury he sustained in the United Rugby Championship win over Connacht in Galway.
Augustus left the field midway through the second half of his team’s 29-24 success at Dexcom Stadium and Ulster say the damage is “significant”.
The former Northampton Saints number eight has initially been ruled out of Friday’s URC match with Munster in Belfast.
Meanwhile Ethan McIlroy’s injury woe has continued as he faces a further spell out of action after picking up a rib injury in Ballynahinch’s Senior Cup Final victory over Instonians.
Eric O’Sullivan (hamstring), Matthew Dalton (knee), Iain Henderson (back) and Rob Herring (knee) have all resumed team training and their availability for selection will be assessed through training this week.
Ulster sit fifth in the URC table, three points below second-placed Munster, so have the opportunity to leapfrog their Irish interprovincial rivals in the table with a win at Affidea Stadium.