Penney has made just three changes from the side that drew with Ospreys, all those up front and more specifically in the back five.
Not surprisingly O'Connell's return forces Billy Holland to the bench and just as unsurprisingly Donncha O'Callaghan gets to partner him while in the backrow Sean Dougall returns to the starting line-up for the first time since the January 9th League encounter with Edinburgh.
The backline remains the same as does the front row while Niall Ronan is included in the match day squad for the first time since November.
Short just five front line players, Conor Murray, Donnacha Ryan, Peter O'Mahony and the injured pair of Keith Earls and Luke O'Dea, it's a selection that gives due cognisance to the challenge faced on Saturday and the importance of the game.
There's only one play off place within Munster's reach and they vie for that fourth spot with Ospreys and Scarlets so all eyes will be on the Stadio XXV Aprile and Liberty Stadium tomorrow night when Scarlets play Zebre and Ospreys take on Dragons.
But while those games will give Munster a clearer understanding where they stand, before a ball is kicked this weekend, they know exactly what's required from them in Musgrave Park on Saturday evening.
Munster: F Jones; D Howlett, C Laulala, J Downey, D Hurley; R O'Gara, C Sheridan; D Kilcoyne,D Varley, S Archer; Donncha O'Callaghan, P O'Connell; T O'Donnell, S Dougall, J Coughlan. Replacements: M Sherry, W du Preez, BJ Botha, B Holland, N Ronan, D Williams, I Keatley, I Dineen.