Thomas Butler spent his youth playing for local sides close to his north Dublin home. After impressing in central midfield for Ireland Under-15s against England he was signed by Sunderland where he stayed six years. During his time at Sunderland his chances were limited though in his 35 appearances he did do enough to gain two full caps for the Republic of Ireland. His time at Sunderland ended in acrimonious fashion and he went to play for a while at Dunfermline before the Scottish Premier League side released him in January 2005. He signed for Pools on a short term contract in March 2005. A skilful, right footed midfielder who has spent most of his career on the left wing, Butler started in fine style when, after a couple of brief substitute appearances, he scored on his full debut against Swindon Town. He signed a longer term contract in the summer of 2005 and started the following season in good form. However as the season progressed a couple of niggling injuries and a dip in form led to Butler being a frustrating figure at times. As Pools faced up to life in League Two following relegation in 2005/06, Butler had a transfer request granted by the club and he joined Swansea City in July 2006.