 Complete the following phrase:  Williamson played one year for the Steelers in the National Football League in 1960. Next, he moved to the new American Football League. Williamson played four seasons for the AFLs Oakland Raiders, making the AFL All-Star team in 1961, 1962, and 1963. He also played three seasons for the AFLs Kansas City Chiefs. During his period of playing for the Chiefs, Williamson became one of footballs first self-promoters, nurturing the nickname The Hammer because he used his forearm to deliver karate-style blows to the heads of opposing players, especially wide receivers. Before 