Ireland's injury worries mean coach Eddie O'Sullivan has named three hookers in his 24-man squad for their opening RBS 6 Nations Championship match against Wales on February 4.
Munster's Frankie Sheehan and Ulster's Rory Best both have calf injuries and so Jerry Flannery has been included alongside them.
Leinster lock Malcolm O'Kelly also has a knee injury, so O'Sullivan has also selected four second-rowers.
"Malcolm's knee injury is still a concern for us and we have allowed some more time for it to respond further to treatment," said O'Sullivan.
"Both Rory and Frankie are carrying slight calf strains, so we have named three hookers to give us some back-up in that area."
Ireland squad for RBS 6 Nations opening match against Wales on February 4:
Forwards: N Best (Ulster), R Best (Ulster), S Best (Ulster), S Easterby (Llanelli), J Flannery (Munster), J Hayes (Munster), M Horan (Munster), D Leamy (Munster), D O'Callaghan (Munster), P O'Connell (Munster), M O'Driscoll (Munster), M O'Kelly (Leinster), F Sheahan (Munster), D Wallace (Munster)
Backs: I Boss (Ulster), G Dempsey (Leinster), G D'Arcy (Leinster), D Hickie (Leinster), G Murphy (Leicester), B O'Driscoll (Leinster), R O'Gara (Munster), P Stringer (Munster), A Trimble (Ulster), P Wallace (Ulster)
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