Cahir's O'Donnell suffered a dislocated hip in Ireland's World Cup warm up match against Wales on Saturday…he has now been ruled out of any participation in the World Cup.
Fellow Tipperary man Alan Quinlan says it's very difficult news for the young rugby star.
Meanwhile, the Ireland squad will return to training at Carton House this morning ahead of their next World Cup warm-up match against Scotland.
After the work-out, the Irish coaching staff are expected to issue an injury update on the fitness of Andrew Trimble, who is set for precautionary scans on the foot injury that he suffered during last weekend's win over Wales in Cardiff.
