O'Brien made his debut for Cheshire in the 1970 Minor Counties Championship against the Yorkshire Second XI.
Prior to playing for Cheshire O'Brien had represented Lancashire County Cricket Club at Colt and Second team level.
It was for Minor Counties East that he made his overall List A debut for, which came against Essex in the 1977 Benson & Hedges Cup.
[7] During his Benson and Hedges career O'Brien won two Man of the Match Gold Medals against Leictershire and Surrey.
He also made four List A appearances for Minor Counties North,[4] though with limited success.O'Brien also represented Cheshire at Table Tennis and has played golf off a single figure handicap for the last 50yrs.