Born in Subiaco, and growing up in the southern suburbs of Perth, Western Australia, Worsfold attended South Fremantle Senior High School in Beaconsfield, graduating in 1985. Falling into the South Fremantle Football Club's recruitment zone, he played in the club's underage teams, and also played in the Western Australia under-18 team that won the state's first Teal Cup in 1985. Worsfold made his senior WAFL debut for South Fremantle in 1986, and played a total of 19 games in his debut season, leading him to be awarded the Rookie of the Year award by the "Daily News". At South Fremantle, he also won "Player of the Future" and "Best First Year Player" awards in 1985 and 1986, respectively.