Leinster flanker Shane Jennings has been promoted to the starting side in place of David Wallace in Ireland's team to play Australia in Melbourne on Saturday.
David Wallace had picked up a calf strain and following a fitness test this morning, Wallace was ruled out of the game by the Ireland team medical staff.
With Jennings starting at openside for Ireland, his position among the replacements is taken by Stephen Ferris, who was a late call up to the squad for the injured Alan Quinlan.
Interim Ireland coach Michael Bradley said the loss of Wallace was a huge blow for the side, but he expects Jennings to step up and fill the void with ease.
'David has had a very good season with Munster and with Ireland. He played very well last week against the All Blacks so he will be missed,' Bradley said.
'But Shane Jennings is a fine player and this creates an opportunity for him.'
'Shane is a quality player and it will be a big test for him.'
Ireland captain Brian O'Driscoll was bitterly disappointed at losing a player of Wallace's experience, but said there was enough quality in the side to cover for him.
'We are quietly confident that we will cause them a few problems,' O'Driscoll said.
'We have got two very good playmakers in Ronan (O'Gara) and Paddy (Wallace) and hopefully they will be able to run a line or two.'
While the battle in the halves will go a long way in deciding the winner of the clash, O'Driscoll believes Ireland need to control the tempo up front to come out victorious.
'Physicality is what wins games,' O'Driscoll said.
'It's often talked about skill levels and tactics and everything, but if you win collision zones whether you have the ball or not, if you win more than 50% of them, you are off on the right foot.
'There have been games when we have played as considerable underdogs and we have just gone out and overpowered the opposition and I think if you need to do that every time you go out and play.
'It's a hell of a lot harder to defend than to attack and it starts from one to eight. Packs win games and if we win the game tomorrow I am sure it will be largely down to our front eight.'
The Ireland team for the one off test match with Australia in Melbourne on Saturday, kick off 11.05am Irish time:
Robert Kearney, Shane Horgan, Brian O'Driscoll, Paddy Wallace, Tommy Bowe, Ronan O'Gara, Peter Stringer;
Marcus Horan, Rory Best, John Hayes, Donncha O'Callaghan Paul O'Connell, Denis Leamy, Shane Jennings, Jamie Heaslip
Replacements:
Jerry Flannery, Tony Buckley, Mick O'Driscoll, Stephen Ferris, Eoin Reddan, Geordan Murphy, Girvan Dempsey
