John Felix Rowser (born April 24, 1944) was an American football player. He played college football for the University of Michigan as a halfback and cornerback from 1963 to 1966. He also played professional football as a defensive back for ten seasons in the National Football League (NFL) from 1967 to 1976. He was a part of the Green Bay Packers Super Bowl II championship team. During his 10 years in the NFL, Rowser appeared in 127 games, 79 as a starter, and intercepted 26 passes for 444 return yards and four touchdowns. He also recovered six fumbles.