Karl Anthony Duguid (born 21 March 1978) is an English footballer who plays as a midfielder or as a defender for Stanway Rovers. He is best known for spending the majority of his career playing for Colchester United where, over two stints, he made in excess of 400 league appearances. He also played for Plymouth Argyle before finishing his career at Colchester, where he became a coach following his retirement in 2014.