U.S. Army 1st Lt. Robert Kalsu, 101st Airborne Division soldier, from Oklahoma City, Oklahoma, was drafted into the NFL before enlisting into the Army in 1968.
He is known for being the only professional football player to lose their life in the Vietnam War.
Kalsu was killed when his unit came under enemy mortar fire in Thua Thien, Vietnam during the Battle of Fire Support Base Ripcord on July 21, 1970. He received the Bronze Star Medal for his actions in support of the U.S. Army.
A part of the honors he has received include honorary buildings and a 1999 Emmy nominated film.