▁appearance ▁at ▁either ▁She ff ield ▁United ▁or ▁Don c aster ▁Ro vers ▁before ▁dr ifting ▁into ▁non - le ague . ▁Following ▁a ▁switch ▁to ▁business ▁he ▁has ▁since ▁held ▁a ▁number ▁of ▁positions ▁before ▁taking ▁over ▁at ▁R angers , ▁including ▁a ▁period ▁as ▁Chief ▁Executive ▁of ▁She ff ield ▁United . ▁ ▁Football ▁career ▁Green ▁started ▁his ▁football ▁career ▁as ▁a ▁school boy ▁with ▁She ff ield ▁United ▁before ▁playing ▁reserve ▁team ▁football ▁at ▁Don c aster ▁Ro vers . ▁He ▁left ▁Don c aster ▁without ▁breaking ▁into ▁the ▁first ▁team ▁and ▁emb ark ed ▁upon ▁a ▁career ▁in ▁non - le ague ▁football ▁with ▁teams ▁like ▁Alf re ton ▁Town ▁where ▁he ▁made ▁ 4 0 ▁appearances . ▁A ▁brief ▁return ▁to ▁the ▁Football ▁League ▁with ▁Bar ns ley ▁resulted ▁in ▁him ▁again ▁failing ▁to ▁make ▁the ▁first ▁team ▁returning ▁to ▁non - le ague ▁football . ▁He ▁had ▁sp ells ▁with ▁Fr ick ley ▁Athlet ic , ▁G ains borough ▁Tr inity , ▁Go ole ▁Town ▁and ▁Ch el ten ham ▁Town ▁who ▁signed ▁him ▁for ▁£ 5 0 0 ▁from ▁Go ole . ▁ ▁She ff ield ▁United ▁F . C . ▁Green ▁was ▁officially ▁appointed ▁chief ▁executive ▁of ▁She ff ield ▁United ▁in ▁February ▁ 1 9 9 6 ▁by ▁chairman ▁Mike ▁Mc Donald ▁following ▁his ▁take ▁over ▁of ▁the ▁club , ▁although ▁in ▁reality ▁Green ▁had ▁been ▁operating ▁in ▁that ▁role ▁since ▁September ▁ 1 9 9 5 . ▁It ▁was ▁a ▁period ▁of ▁rapid