Smitty Duke attended the University of Dallas where he was a two-time All-American pitcher on the baseball team. He graduated in 1964 with an education degree and turned his athletic talents to volleyball. Duke played for the US in a 1965 North American Tour, at the 1966 World Championships, then in 1967 helped them win a gold medal at the Pan American Games. After the 1968 Olympics, he continued to compete on the USA volleyball team, winning a silver medal at the 1971 Pan-Ams. He later played for the Dallas YMCA in his hometown, and played professional volleyball into the late 1970s. He later taught school and coached volleyball in Irving and Nacogdoches, Texas, and at his alma mater.