Iain Henderson has been ruled out of Ulster's Heineken Champions Cup game with Toulouse.
The lock sustained a knee injury in Ireland's 31-16 victory over Scotland on Saturday in the Autumn Nations Cup.
Ulster say Henderson needs to a see a specialist regarding the injury and is out of Friday's game at Kingspan Stadium as a result.
Billy Burns - who missed Ireland's final two games of the autumn - has also been ruled out of the Toulouse clash as he's yet to shake off his groin injury.
Winger Rob Lyttle sustained a back injury in last week's Guinness PRO14 victory away to Edinburgh and is another confirmed absentee.
They join Louis Ludik (concussion), Luke Marshall (knee), Rob Baloucoune (hamstring), Will Addison (back), Angus Curtis (knee) and Tom Stewart (hamstring) on the sidelines.
Toulouse will arrive into Belfast later this week a side in form.
They sit second in the Top 14 - behind Ronan O'Gara's La Rochelle - following a 24-20 win away to Bayonne on Saturday.