He first umpired in the Moorabbin Saints Junior Football League in 2006.

In 2014, he was added to the Australian Football League umpiring list, and made his debut in Round 7 of that year, in a match between Hawthorn and St Kilda at the Melbourne Cricket Ground.

He officiated in his 50th AFL game in Round 4, 2017, in Greater Western Sydney's 31-point win over Port Adelaide at Manuka Oval.

[1] In 2024, O'Gorman began umpiring every week as of round 7.

He umpired his 200th game in the round 3 match between Essendon and St Kilda in 2024.