The best season for Cunningham was in 1959, when he batted .345 to finish second to Hank Aaron for the National League batting title. He finished his career with a .291 batting average over 1,141 games spread over a 12-year career.
Cunningham was traded from the Cardinals to the White Sox after the 1961 season in exchange for long-time star Minnie Miñoso. Although his first season as the White Sox first baseman was successful, Cunningham would never fully recover from a broken collarbone suffered in a collision on June 3, .