Despite the upheaval, O'Gara expects the European Cup champions to flourish in the new era.
He told the Irish Examiner: "We will miss Declan (Kidney) for all of the things he brings to the game, for the things he brought to Munster.
"But Tony is a very good technical coach, and I think the age-profile of this squad is such that we're ripe to benefit from his type of technical coaching."
He insisted McGahan will have 100% support. He added: "There are no barriers in this Munster squad. It's not an issue; honesty prevails throughout and that will always be the way. It will never change."