Smart made his senior debut in 1988 in the SANFL with South Adelaide Football Club and was a member of the Adelaide Crows squad for their inaugural season in 1991. Smart was named at full-back for Adelaide's Round One match against Hawthorn, standing superstar full-forward Jason Dunstall. On his AFL debut Smart collected six kicks, nine handballs and grabbed six marks.
One of the most famous incidents attributed to Smart's career was during the 1992 pre-season, when the Crows organised a session to walk over hot coals. Smart suffered severe burns to his feet but returned to play football soon after.
Smart was one of the key players in Adelaide's resurgence under Malcolm Blight, and in the 1997 AFL Grand Final against St Kilda, he had the honour of kicking the final goal of the match as Adelaide won their first AFL premiership. He was also a member of the Crows team which won the 1998 AFL Grand Final, the Crows becoming the first team since Hawthorn in 1988 and 1989 to win back-to-back premierships.