If you're a short guy like me, southpaw Bobby Shantz should be your hero.
At 5'6" and 139 pounds, Shantz couldn't have looked particularly dominating. Ever hear the (apocryphal) story of pitcher Stu Miller being blown off the mound in the 1961 All-Star Game at Candlestick Park? Shantz would have been blown into the Bay.
Nevertheless, he is by far the champion undersized pitcher of all time.
His lifetime record was 119-99, with a 3.38 ERA. He fanned 1,072 and won eight Gold Gloves. Shantz pitched most of his games for the Philadelphia and Kansas City A's, the Yankees, the Cardinals and also had brief stints with the Cubs, Pirates, Colt .45s (later the Astros) and the Phillies.
Shantz's major league career lasted 16 seasons, a notable achievement for a pitcher of any size. His best season came with the A's in 1952, when he went 24-7 with an ERA of 2.48. He hurled 27 complete games, five shutouts and struck out a career-high 152 batters. And smack in the middle of an era of huge talents like Doby, Rosen, Mantle and Berra, Shantz was named MVP of the American League.