Career
He previously played for the St. George Illawarra Dragons. He primarily plays as a prop. Born in Sydney, New South Wales, O'Brien is of Māori descent and played his junior football for Hurstville United, before being signed by the St. George Illawarra Dragons.
Early career
In 2008, O'Brien played for the St. George Illawarra Dragons' NYC team, before giving up the game in early 2009. In October 2013, he played for the New South Wales Country Residents team that toured South Africa. In 2014, he joined the Illawarra Cutters in the New South Wales Cup.
On 26 June 2014, he signed a 2 1⁄2-year contract to return to the St. George Illawarra Dragons effective immediately. 2015
In Round 1 of the 2015 NRL season, O'Brien made his NRL debut for the Dragons against the Melbourne Storm. On 26 August, he signed a 1-year contract with the Parramatta Eels starting in 2016, after being released from the final year of his Dragons contract.
