Great club and amateur performances have led to his Western Province sevens and Currie Cup debuts.
[citation needed] O'Brien played club rugby at Western Province club sides Helderberg and Villager before being included in Western Province's wider training group prior to the 2013 Currie Cup Premier Division.
[2] He failed to make an appearance for them, but joined Kimberley-based side Griquas for that competition.
[4] In total, he made nine appearances for Griquas in 2013, seven in the Currie Cup Premier Division and two in the post-season promotion/relegation series against the Pumas.
In 2014, he returned to Cape Town to play for UWC in the 2014 Varsity Shield competition, scoring one try in his four starts for the side.