Gary Roger Lewis (February 22, 1942 – December 12, 1986) was a professional American football running back in the National Football League. He played seven seasons for the San Francisco 49ers (1964–1969) and the New Orleans Saints (1970). Lewis was one of three 1964 San Francisco 49ers teammates (with Bob Waters and Matt Hazeltine) who died of amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's Disease.