Ireland have recalled centre Kevin Maggs for Saturday's RBS 6 Nations showdown against France following Gordon D'Arcy's failure to recover from his hamstring injury.
D'Arcy sustained the damage in his side's tournament opener against Italy but his rehabilitation has slowed over the past two weeks.
Ireland coach Eddie O'Sullivan said: "Gordon is not fit. He played for Leinster on Sunday and we were confident that if he got through the game he would be okay.
"But he couldn't give as much as he wanted and at that juncture we knew he it wasn't right for France."
Maggs' return is the only change to the line-up which beat England nine days ago and he wins his 68th cap at the expense of Shane Horgan who was ruled out last week with a fractured thumb.
Harlequins back Gavin Duffy takes Maggs' place on the bench while skipper Brian O'Driscoll starts after the bruised elbow he suffered against England forced him to withdraw from the IRB Rugby Aid tsunami fund-raising game on Saturday.
O'Driscoll will captain the side for the 21st time on Saturday while his Leinster team-mate Denis Hickie wins his 50th cap.
Ireland team to play France in the RBS 6 Nations at Lansdowne Road on Saturday:
G Murphy (Leicester); G Dempsey (Leinster), B O'Driscoll (Leinster, capt), K Maggs (Ulster), D Hickie (Leinster); R O'Gara (Munster), P Stringer (Munster); R Corrigan (Leinster), S Byrne (Leinster), J Hayes (Munster), M O'Kelly (Leinster), P O'Connell (Munster), S Easterby (Llanelli), J O'Connor (Wasps), A Foley (Munster).
Replacements: F Sheahan (Munster), M Horan (Munster), D O'Callaghan (Munster), E Miller (Leinster), G Easterby (Leinster), D Humphreys (Ulster), G Duffy (Harlequins).
England Under-20s head coach Martin Haag was full of praise for his World Rugby Under-20 Championship-winning side after Harry Mallinder inspired them to a 45-21 win over their Irish counterparts and a third title in four years.