Originally from the Mordialloc-Braeside Football Club, Cristian O'Brien then played for the Southern Stingrays Under 18's (TAC Cup), and represented Victoria in the 1991 Teal Cup, In 1991 he also played for the Melbourne Football Club's Under 19's, progressing to their Reserves the following season.
He joined Norwood after being delisted by Melbourne at the end of the 1992 season.
O'Brien made his SANFL debut in Norwood's opening game of the 1993 season. Played at the Parade, the Redlegs defeated Sturt in a high scoring encounter : 21.16 to 18.6.
Strong and athletic with a long kick, he could play at either end of the ground. O'Brien impressed in his first year in the SANFL and as a result Geelong selected him in the 1993 AFL Mid-Season Draft. Choosing to play out the season at the Parade, O'Brien was named on a half-forward flank in the 1993 Grand Final side which was defeated by Woodville-West Torrens.
He joined Geelong for the 1994 season and played two AFL games in his time with the strong Cats line-up.
Returning to Norwood in 1997, he was named best player in the Reserves Grand Final side that lost to Port Adelaide by one point.
In 1998 he was Norwood's leading goal-kicker in the League side, and played his 50th senior game the following year.
O'Brien later played for, and coached, the Rye Football Club (Mornington Peninsula, Victoria).
R Cialini Aug 2016