Kennelly became the first Irishman to win an AFL Premiership medal in 2005, after playing all 26 games for the Sydney Swans that year, including his 100th AFL game in the preliminary final against . He was reportedly earning $750,000 (350,000 Euro), while playing for the Sydney Swans. The hype in Australia surrounding Kennelly's appearance in the AFL Grand Final was so much that Network Ten sent out its usual game-day boundary rider, Andrew Maher, over to County Kerry to visit Tadhg's family for the week and watch the Grand Final with them. Kennelly also appeared in the 2006 Grand Final, but the Swans lost 85–84 to the West Coast Eagles.