Sheahan joined the Winnipeg Blue Bombers in the 2023 season after he was selected eighth overall in the 2023 CFL Global Draft.

[3] He won the starting job as punter by beating out veteran Marc Liegghio and fellow global player Karl Schmitz during the Bombers' 2023 preseason.

[3] He grew up in Bendigo, Australia and initially he played Australian Rules Football.

Sheahan played for the Essendon Bombers a team in the Australian Football League but moved to the United States for college at the end of his contract and took up punting for the University of California, Berkeley.

[3] Sheahan's master's degree was focused on the administrative side of education and he aspires to be an athletic director at an American college.