Paul O'Connell and Damien Varley have both been ruled out of the RaboDirect PRO12 semi-final clash with Ospreys at the Liberty Stadium on Friday.

O'Connell injured his left knee against Ulster is expected to be sidelined for 4-6 weeks, while Varley suffered an ankle sprain but could yet prove his fitness for the final should Munster win on Friday.

Ronan O'Gara, who has been out of action since sustaining a leg injury in the Heineken Cup quarter-final against Ulster, is expected to train tomorrow and could be named in the squad tomorrow evening.