Lawrence Joseph Gagner (born December 30, 1943) is an American former college and professional football player who was a guard in the National Football League (NFL) for five seasons during the 1960s and 1970s. Gagner played college football for the University of Florida, and was recognized as an All-American. He was a second-round pick in the 1966 NFL Draft, and played professionally for the Pittsburgh Steelers and the Kansas City Chiefs of the NFL.
Gagner was born in Cleveland, Ohio in 1943. He attended Seabreeze High School in Daytona Beach, Florida, where he was a standout two-way prep player for the Seabreeze Sandcrabs high school football team. The Sandcrabs posted a 19–2–1 overall win-loss record during Gagner's junior and senior years, and laid claim to the state football championship his junior year. In 2007, forty-six years after he graduated from high school, the Florida High School Athletic Association (FHSAA) named Gagner to its "All-Century Team," recognizing him as one of the thirty-three greatest Florida high school football players of the last 100 years.