O'Connell wasn't named in the extended squad announced on Wednesday as McGahan waited to see how the squad captain came through what was only his second full contact session yesterday since picking up the ankle injury against Leinster a month ago.
As it transpired, O'Connell showed no ill effects from his exertions and not surprisingly is included on a particularly strong looking bench alongside Marcus Horan, John Hayes and Peter Stringer who between them have over 600 Munster caps.
Commenting on the O'Connell decision, McGahan said, "We thought it prudent to omit Paul from the original squad until we saw how he came through what was only his second serious workout (yesterday) since sustaining the injury. He reported no ill effects today so we're delighted to be able to name him in the squad."
When he sustained the injury in the April 2nd encounter, it was expected that his re-appearance would likely be in the latter stages of the Magners and McGahan was quick to heap praise on his backroom team and the player himself.
"I think the Munster medical and fitness staff deserve huge credit for having him back in the match day squad at this stage. But it also demonstrates Paul's professionalism, dedication to his sport and commitment to Munster."
Munster: F Jones; D Howlett, L Mafi, P Warwick, K Earls; R O'Gara capt, C Murray; W du Preez, D Varley, T Buckley; D O'Callaghan, M O'Driscoll; D Leamy, D Wallace, J Coughlan. Replacements: M Sherry, M Horan, J Hayes, P O'Connell, D Ryan, P Stringer, S Tuitupou, J Murphy.