King became the Reds' third string catcher, playing behind future Hall of Fame member, Johnny Bench and Bill Plummer. On July 1, 1973, while the Reds trailed their National League Western Division rivals the Los Angeles Dodgers by 11 games in the standings, King hit a ninth inning, pinch-hit, walk-off home run against Don Sutton. King's home run was cited by Reds' manager Sparky Anderson, as a turning point in the season. Starting with the win on King's home run, the Reds gained momentum and went on to post a 60–26 record for the remainder of the season to overtake the Dodgers and win the division championship. King hit three pinch-hit home runs to either tie or win games for the Reds that season. In the only postseason appearance of his career, King had one hit in three at bats as the Reds lost to the New York Mets in the 1973 National League Championship Series. King played his final major league game on October 1, 1974 at the age of 30.