Sullivan began his career playing junior football at St Kevin's College in 2010, playing for the school's U18 side from Year 10 through to Year 12. In 2016, Sullivan joined St Kevin's Old Boys in the Victorian Amateur Football Association (VAFA).[1] Transitioning to the Victorian Football League (VFL) in 2019, he signed with Footscray.[2] Sullivan's consistent performance led to him being named team captain, and winning Footscray's Best and Fairest awards in both 2022 and 2023, as well as being awarded the 2023 Coaches MVP Award, attributed to his average of 30.9 disposals and 7.9 clearances per game.[3][4] Sullivan's strong VFL performance in 2023 culminated in finishing third in voting for the J. J. Liston Trophy, and being selected as captain in the 2023 VFL Team of the Year.[5]
AFL career
Despite reportedly garnering interest from AFL clubs Essendon and the Western Bulldogs, Sullivan went undrafted, and worked as an electrician while continuing to vie for selection from a professional club.[6] He was invited to train with Collingwood in the pre-season before the 2024 AFL season[7] and was then signed up during the pre-season supplementary selection period as a mature-age recruit.[8][9] He made his debut in May 2024 against Carlton, coming on as the substitute in the second quarter and kicking a goal with his first kick.[7]