Farrell played in the North Sydney Bears S.G Ball team. Farrell then played in South Sydney's NYC team in 2009 and 2010.
2010
In round 22 of the 2010 NRL season, Farrell made his NRL debut for the South Sydney Rabbitohs against the Wests Tigers at centre, scoring a hat-trick in a golden point thriller. Farrell scored the winning try right on full-time, the Rabbitohs winning 34-30 at ANZ Stadium. Farrell scored 5 tries from 5 appearances in his debut season. On 31 August, Farrell was named at centre in the 2010 NYC team of the year.
On 18 March 2011 Farrell extended his contract with South Sydney until the end of the 2013 NRL season. Farrell played 23 matches and scored 12 tries for South Sydney in 2011.
In May, Farrell agreed to a three-year contract with the St George Illawarra Dragons starting from 2014. Farrell played in 15 matches and scored 6 tries in his last year with the Rabbitohs. Farrell also spent some time playing in the NSW Cup for Souths feeder side the North Sydney Bears making 9 appearances and scoring 4 tries.
2014
In February, Farrell was selected for the Dragons inaugural Nines squad. In round 1, he made his club debut for St. George against the Wests Tigers, playing at centre in the 44-24 win at WIN Stadium. In round 6, against the Melbourne Storm at AAMI Park, Farrell scored his first club try for St. George in the last minute 24-28 loss. During the match Farrell suffered a pectoral muscle injury and later received the same injury in a New South Wales Cup match for the Illawarra Cutters, ending his season. Farrell scored one try from 6 games in his first year with St. George Illawarra.
2015
Farrell finished the 2015 NRL season with him playing in 13 matches for the club, playing on the wing and in the centres. Farrell announced he would retire from rugby league due to a complex and ongoing back injury sustained near the end of the 2015 NRL season. Unfortunately like many NRL Players injury prematurely ending a promising career.
Post playing
In June 2017, Farrell was interviewed by former rugby league player Denan Kemp and revealed he was in severe debt due to the NRL and St. George Illawarra club failing to pay out insurance money which was owed to him. Farrell claimed that he was forced to sell his house which made him feel “at the lowest of the low". In 2018, Farrell was appointed head coach of the Nowra-Bomaderry Jets.
