Farrell studied and played ice hockey at St. Mary's College from 1895 until 1896. While there, he met future Shamrocks' players Harry Trihey, Fred Scanlan and Jack Brannen. In 1897, the four joined the Montreal Shamrocks. Farrell, along with Trihey, Scanlan and Brannen would form an impressive offensive line for the Shamrocks.
He wrote the first ever book on ice