George Mitterwald was primarily a back-up catcher for 11 seasons with the Twins and the Cubs. After 7 seasons with the Twins, he was traded to the Cubs in December 1973 for Randy Hundley. Hundley had a solid career with the Cubs but apparently the Cubs knew when to send him out. As a Twin, Hundley only played in 28 games and hit .193. He was released by the Twins less than a year after the trade.
Mitterwald served as a back-up to Steve Swisher until 1977 when Mitterwald started 102 games for the Cubs. As a Cub for 4 years, Mitterwald hit .216 with 26 home runs and 125 RBI’s. On April 17, 1974, Mitterwald hit 3 home runs in one game. He is one of about 500 major league ball players to accomplish this feat.
After the 1977 season, Mitterwald became a free agent and signed with Seattle in the spring of 1978. However, he never played in the majors after 1977.