contract with Dundee in January 2016. On 22 March 2016, he signed a new three-year contract. In June 2017, O'Dea was named as permanent club captain by Dundee, having performed the role during the previous season in place of the injured James McPake. On 7 May 2019, O’Dea announced in a long-form announcement on his Twitter account that he would be leaving Dundee at the end of the season, and that this would mark the conclusion of his last season as a full-time professional footballer. East Kilbride O'Dea signed for his local side East Kilbride in May 2019 but left in August without making a single Lowland league appearance for the club. O'Dea left to focus on his coaching commitments with Motherwell full time. International career After playing for the Irish under-19 and under-21 teams, O'Dea was called up to the international squad within a year. Promoted to the Irish under-21 international squad by manager Don Givens on 3 March 2007, he was the team captain. Less than a week later, O'Dea was named to the international squad for Ireland's UEFA Euro 2008 qualifying Group D matches on 24 and 28 March. On 13 May 2008, he was listed on Giovanni Trapattoni's first squad as Ireland's manager for the 2010 FIFA World Cup qualification – UEFA Group 8 matches against Bulgaria and Italy. O'Dea made his senior-team debut on 8 September 2009 in a 1–0 friendly win over South Africa at Thomond Park in Limerick as a 60th-minute substitute for Paul McShane. After a match against the Czech Republic, O'Dea said he dreamed of being named to the Irish squad for UEFA Euro 2012. Although he was on the roster for the tournament in Poland and Ukraine, he did not appear; the Irish were eliminated from the group stage. O'Dea scored his first senior goal for Ireland, an 88th-minute header, in a World Cup qualifying match against the Faroe Islands on 16 October 2012 which Ireland won 4–1. Playing style O'Dea's manager at Toronto FC, Paul Mariner, described him as a "different specimen" with "fantastic habits" and a good leader. According to Miloš Kocić, he is a good defender of set pieces. Coaching career O'Dea was appointed to a coaching position with Motherwell in May 2019. In September 2019 he left Motherwell and returned to Celtic to become manager of their under-18s. In October 2021 he was promoted to coach