Peter Stringer who recovered from injury to play in the closing stages of the Sale game returns at the expense of Tomas O'Leary, Trevor Halstead takes over at inside centre - Gary Connolly moving to his more familiar 13 slot - and Anthony Horgan comes onto the wing in place of Anthon Pitout.
For Munster it's another one of those win or bust games as they attempt to recover from the luckless start of last weekend. In Stockport last Friday they really did enough to deserve at least a bonus while a win did not look beyond them right up to the time they conceded that Jason Robinson try from a promising attacking move.
However, there are no points, bonus or otherwise for maybes and Munster find themselves bottomof the pile in Pool One and facing an awesome looking French side.
Nor will the Thomond Park factor hold the same fear for Castres as it might for others,with the French having trod this path so often before, as Kidney mentioned at the press conference in Musgrave Park. "We've played them that often now it's almost like a local derby at this stage, " he said."
Munster: Shaun Payne; John Kelly, Gary Connolly, Trevor Halstead, Anthony Horgan; Ronan O'Gara, Peter Stringer; Marcus Horan, Jerry Flannery, John Hayes; Donncha O'Callaghan, Mick O'Driscoll; Denis Leamy, David Wallace, Anthony Foley capt
Replacements: Denis Fogarty, Federico Pucciariello, Trevor Hogan, Stephen Keogh, Tomas O'Leary, Jeremy Manning, Barry Murphy.