In each season from 1961 to 1973, Williams hit at least 20 home runs and drove in 84 or more runs. His batting swing was smooth and efficient, with quick wrist action that allowed him to hit for both average and power despite his slender frame. Early in his career, this earned him the nickname "Sweet-Swinging Billy Williams," sometimes shortened to "Sweet Williams" or "Sweet Billy". His nickname was later referenced in the subtitle of his autobiography. He was also nicknamed "Sweet-Swinging Billy from Whistler," in reference to his birthplace in Alabama. His home run feats included 3 homers in one game and 5 homers in 2 consecutive games. Twice in one season, Williams belted 4 extra-base hits in a game.