Despite making his MLB debut as a 31-year-old rookie, Kinder enjoyed a career which lasted over a decade. He is one of few pitchers in baseball history who won or saved a combined total of at least 200 games, and who were primarily starters for at least a third of their career.
Kinder was among the best starting pitchers in the American League in 1949, going 23–6 and leading the league in shutouts (6) and a .793 winning percentage, with a 130 adjusted ERA. In fact, Kinder's ERA+ for his four years as a starter were 87, 117, 130 and 115. Then, in 1951, the Red Sox, desperate for a relief pitcher, moved him to the pen, where he shone as the best reliever in the AL until 1955.
In his 12-year career, Kinder compiled a 102–71 record with 749 strikeouts, a 3.43 ERA, 56 complete games, 10 shutouts, 102 saves, and 1479.2 innings pitched in 484 games.
On May 17, 1947, a seagull flew over Fenway Park and dropped a three-pound smelt on Kinder while he was pitching for the St. Louis Browns. Nevertheless, Kinder beat Boston 4–2.
Twice led league in winning percentage (1949, 1951)
Led league in shutouts (1949)
Twice led league in games pitched (63, 1951; 69, 1953)
Twice led league in saves (1951, 1953)
Pitched a 10 inning scoreless relief win-game (1951) (On July 12, 1951, Kinder took over to start the eighth inning and held the Chicago White Sox scoreless for 10 innings. The Red Sox finally scored a run in the 17th inning to win, 5–4.)
