Haynes was a first round draft pick of the Giants in the 1980 NFL Draft and was instrumental in their 1981 playoff run, which saw the Giants make the playoffs for the first time since 1963.
Mark Haynes has one career touchdown on an interception return, which took place during the 1987 season. In the 1984 season Haynes had seven interceptions and was named first-team All-Pro. He ended his career with seventeen total interceptions and four fumble recoveries.
↑Neft, David S. & Cohen, Richard M. The Football Encyclopedia: The Complete History of Professional NFL Football from 1892 to the Present, pp. 845, 873, 913. St. Martin's Press, 1991. ISBN 0-312-05089-5.