The 5’6″ 139-lb Shantz broke in spectacularly, winning a 13-inning game in relief, pitching nine hitless innings along the way while giving up one run and two hits overall. He was handicapped by manager Connie Mack, a former catcher who wouldn’t let Shantz use his knuckleball and was predisposed against small pitchers. When Mack finally retired after the 1950 season, Jimmy Dykes took over the club and gave the little lefthander more rest between starts; Shantz blossomed. Finally allowed to use his knuckler, and with a curveball that Ted Williams called the best in the AL, Shantz learned to change speeds and went 18-10 for the 70-84 Athletics.
Shantz reached the peak of his career in 1952, going 24-7 for a fifth-place team to win the MVP award in a landslide. He led the AL in wins, winning percentage, and fewest walks per game (2.03), and finished third with a 2.48 ERA and 152 strikeouts, tied for third with five shutouts, second with 27 complete games, fourth with 255 innings, and fifth in fewest hits per game (7.39).
Plagued by injuries for most of the next four seasons, Shantz went to the Yankees in a 12-player deal before the 1957 season and made a great comeback that year, leading the AL with a 2.45 ERA while going 11-5. After that, he was used more frequently in relief, and contributed 11 saves to the 1960 pennant winners before being traded to the Pirates, who had defeated New York in the World Series; Shantz saved Game Two for the Yankees. He bounced around the NL after that, effective until his last year.
Shantz won Gold Gloves in the first four years of the award (1957-60). His brother Billy was a catcher for the A’s in 1954-55 and in one game for the 1960 Yankees