Not quite sure what you mean there. In my opinion, bringing Wilson into the squad means O'Shea will more than likely play full back, with Wilson as back up for the centre halves in the squad. Coleman's inclusion is as cover on the right for the injured Kelly.
Right now I think the pecking order is:
Left full: Kilbane - Cunningham
Centre half: Dunne - St Ledger - McShane - Wilson
Right Full: O'Shea - Foley - Coleman
With O'Shea providing cover for all positions, playing primarily on the right, the squad is reasonably well stocked in defence.
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