He plays Gaelic football with his local club Castlegregory and was a member of the Kerry inter-county teams during the 90's.
Kerry took the title after a 0–16 to 1–07 win to give O'Mahoney an All-Ireland minor medal.
Wins over Limerick and Clare saw Kerry book a place in the Munster final.
Kerry made no mistake second time out winning 0–12 to 1-07 and gave O'Mahoney a Munster title as captain.
O'Mahoney and Kerry's season came to an end after losing out to Meath in a point in the All-Ireland semi-final.
Im O'Mahony's second All-Ireland final at the Junior grade Kerry faced Roscommon.