Sad how little video exists of even pre-70s greats. Regarding Feller's arm problems after age 29: by then he had been in the majors since age 17.
That video of him was made in 1946, probably his best year. He pitched an incredible 371 innings that year with an ERA of 2.18.
Interesting tidbits on his HS years:
" had one overriding desire: to play baseball. His father, who had been a semi-professional pitcher in his younger days, encouraged Feller's interest in baseball. He built a pitching mound and set up a home plate between the house and the barn.
Young Feller spent hours a day throwing pitches to his dad and building up his arm strength. In the winter, father and son would play catch inside the barn."
"As a child, Feller always wanted to play baseball with older kids. When he was 12, he helped his father build their own baseball field on the farm, complete with a grandstand.
His father started a team, with his son as the pitcher, and charged 35 cents admission. Feller grew into a strong, strapping teenager, who looked older than his age. Sometimes more than a thousand people came to the farm to see him pitch. By the time he was in high school, major league scouts had heard about his fastball."
"The Indians brought Feller to Cleveland during the 1936 season. In July he pitched in an exhibition game against the St. Louis Cardinals.
Feller, who had never pitched a single game in the minor or major leagues, looked raw and nervous. But, using only a fastball, he struck out eight batters in three innings. The Indians immediately put him into their bullpen, even though he was only 17 years old. In his first start, on August 23, he struck out 15 and beat the St. Louis Browns, 4-1."
"The amazing teenage pitching sensation was an instant drawing card for the Indians. When he pitched, attendance would rise by about 10,000 fans."
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