Mark Melville Williams (born 21 August 1958) is a former Australian rules football player and coach. As a player, Williams represented in the South Australian National Football League (SANFL) as well as Collingwood and Brisbane Bears in the Australian Football League (AFL) from the 1980s to the 1990s. One of several successful father-son combinations in Australian rules football, Williams became a successful coach after finishing his playing career, leading to their first AFL premiership in 2004. Playing career South Australian National Football League (SANFL) West Adelaide The son of South Australian football legend Fos Williams, Williams playing career began with ,In the SANFL league, where his father was serving as coach. He represented West Adelaide on 64 occasions for 37 goals. Port Adelaide (SANFL) Williams then moved to the Port Adelaide Football Club In the SANFL league, becoming one of the stars of the SANFL, where he was part of the 1979 and 1980 Premiership sides. Victorian Football League (VFL)/ Australian Football League (AFL) Collingwood Football Club (1981–1986) After the 1980 season, Williams was recruited by , making his Victorian Football League (VFL) debut in the 1981 season. Williams justified the hype over his recruitment by winning state selection for Victoria as well as the Copeland Trophy. He was named at centre for Collingwood in the 1981 Grand Final against Carlton. Collingwood lost, but Williams was recognised as being among the Magpies' better players on the day. When John Cahill took over as senior coach of Collingwood Football Club after a tumultuous season in 1982, he appointed Williams captain, having previously worked with him at . In 1984, Williams led Collingwood's goalkicking, kicking 53 goals for the season. However, he was unavailable for the Preliminary Final due to injury, and Collingwood went down to eventual premiers by 133 points. Williams remained captain of Collingwood until he left at the end of 1986 after a contract dispute. Brisbane Bears (1987–1990) Williams joined the Brisbane Bears, a new club who joined the Victorian Football League (VFL) league in 1987. He was appointed vice-captain to Mark Mickan at the new club. Williams played three and a half seasons from 1987 until 1990 to a total of 66 games for the Bears, before retiring from the Bears midway through the 1990 AFL season. Return to South Australian National Football League (SANFL) Port Adelaide (SANFL) (1990–1992) Williams returned to Port Adelaide, and finished the 1990