▁and ▁reg ain ▁his ▁fit ness , ▁D uff y ▁returned ▁to ▁action ▁in ▁little ▁over ▁ten ▁weeks ▁after ▁his ▁injury ▁and ▁has ▁since ▁appeared ▁for ▁Republic ▁of ▁Ireland ▁under - 1 9 ▁and ▁under - 2 1 ▁squad s . ▁He ▁was ▁called ▁up ▁for ▁the ▁U 2 1 ▁friendly ▁versus ▁Portugal ▁in ▁March ▁ 2 0 1 1 . ▁ ▁Play ers ▁such ▁as ▁D uff y , ▁James ▁McC lean , ▁Daniel ▁K ear ns , ▁Dar ron ▁Gib son ▁and ▁Marc ▁Wilson ▁had ▁represented ▁Northern ▁Ireland ▁at ▁youth ▁level ▁but ▁later ▁opt ed ▁to ▁play ▁for ▁Republic ▁of ▁Ireland . ▁The ▁I FA ▁disput ed ▁the ▁players ' ▁right ▁to ▁do ▁so ▁under ▁FIFA ▁rules ▁and ▁felt ▁the ▁current ▁rules ▁were ▁a ▁" clear ▁dis adv antage ▁over ▁all ▁other ▁ 2 0 6 ▁Associ ations ". ▁The ▁Irish ▁Football ▁Association ▁took ▁a ▁case ▁to ▁the ▁Court ▁of ▁Ar bitr ation ▁for ▁Sport ▁with ▁the ▁hope ▁of ▁getting ▁FIFA ▁to ▁' u ph old ' ▁the ▁rules . ▁Although ▁D uff y ' s ▁name ▁is ▁often ▁linked ▁with ▁this ▁dispute ▁and ▁the ▁I FA ▁appeal ▁to ▁the ▁Court ▁of ▁Ar bitr ation ▁for ▁Sport , ▁his ▁situation ▁diff ers ▁from ▁that ▁of ▁players ▁such ▁as ▁Dar ron ▁Gib son ▁because ▁of ▁his ▁close ▁family ▁t ies ▁to ▁Don eg al . ▁This ▁means ▁he ▁would ▁have ▁been ▁el ig ible ▁to ▁play ▁for ▁the ▁Republic ▁of ▁Ireland ▁wherever ▁he ▁was ▁born . ▁ ▁On ▁ 1 3 ▁February