John Marshall (born October 2, 1945) is an American football coach. He formerly served as the defensive coordinator for the Oakland Raiders from 2009-2010. Marshall, a coaching veteran of over 40 years, is mostly associated with coaching linebackers. He earned two Super Bowl rings during his time with the San Francisco 49ers, where he was an assistant. Marshall coached linebackers for the Detroit Lions in 2002, where he was on the staff of Marty Mornhinweg. Marshall had previously served as defensive coordinator under Steve Mariucci with the San Francisco 49ers in 1997 and 1998.