Marshall arrived at Glenelg from Plympton High School and made his league debut in 1978, playing primarily as a wingman.
In 1990, Marshall had his best season at Glenelg, taking out their 'Best and Fairest' award and finishing runner-up in the Magarey Medal.
Adelaide signed him up as their oldest recruit for their inaugural AFL season in 1991 and he was one of their best performers in the midfield, averaging 24 disposals a game from his 15 appearances.
He had a particularly strong debut in the club's inaugural game against Hawthorn at Football Park, with two goals and 29 disposals to earn two Brownlow votes as the Crows thumped the eventual season's premiers by 86 points.
He later served as a board member and selector at Adelaide and in 2003 was inducted into the South Australian Football Hall of Fame.