Career
Farrell played as a left back. Farrell most notably made his name at Bray Wanderers over a period of 13 years for whom he was the clubs longest serving player. He began his senior career with Shelbourne in 1988 before enjoying spells with Home Farm, Athlone Town and non-league Elm Rovers.
Farrell joined Bray Wanderers prior to the start of the 1991-1992 League of Ireland season.
During his lengthy career the Carlisle Grounds, Farrell made 335 competitive appearances and scored 5 goals for Bray. The greatest success for Farrell with Bray Wanderers came in 1999 when he helped the Seagulls to FAI Cup victory over Finn Harps following a 2nd replay.
Farrell retired from senior football at the end of the 2004 First Division season with Bray after helping them to a 3rd place finish and promotion to the Premier Division. Farrell made a surprise comeback to League of Ireland football in June 2009 with Shelbourne joining the Tolka Park club as part of their coaching staff
Farrell also registered as a player for Shels and following his retirement 5 years previous, he made his comeback as player at the age of 39 on 10 July 2009 coming on as a 90th minute substitute for Shelbourne in a 1-0 victory over University College Dublin at the Belfield Bowl.