The absence of O'Gara, Jeremy Manning, Rua Tipoki and Kieran Lewis means a place in the squad for Garryowen player Conan Doyle and Development player Tom Gleeson.
League leaders Ospreys were given a further boost ahead of the Munster visit with the news that former Wales skills coach and current US Eagles coach Scott Johnson is about to take over from current coach Sean Holley at the Liberty.
A report in the Western Mail claims that the deal 'has been virtually signed, sealed and delivered' with Ospreys insiders saying it is only a question of dotting the 'i's' and crossing the 't's'.
Munster: D Hurley; D Howlett, B Murphy, L Mafi, I Dowling; P Warwick, T O'Leary; F Pucciariello, J Flannery, J Hayes; D O'Callaghan, P O'Connell capt; A Quinlan, D Wallace, D Leamy. Replacements: D Fogarty, T Ryan, M O'Driscoll, J O'Sullivan, P Stringer, C Doyle, T Gleeson.