Major League Baseball on Mutual

Major League Baseball on Mutual was the de facto title of the Mutual Broadcasting System's (MBS) national radio coverage of Major League Baseball games. Mutual's coverage came about during the Golden Age of Radio in the 1930s, 1940s, and 1950s. During this period, television sports broadcasting was in its infancy, and radio was still the main form of broadcasting baseball. For many years, Mutual was the national radio broadcaster for baseball's All-Star Game and World Series.

Mutual started its baseball coverage in 1935, when the network joined NBC and CBS in national radio coverage. The three networks continued to share coverage of baseball's "jewels" (the All-Star Game and World Series) in this manner through 1938, with Mutual gaining exclusive rights to the World Series in 1939 and the All-Star Game in 1942. In 1949, Commissioner Happy Chandler negotiated a seven-year, US$4,370,000 contract with the Gillette Safety Razor Company and the Mutual Broadcasting System for radio rights to the World Series, with the proceeds going directly into the pension fund. In 1957, NBC replaced Mutual as the exclusive national radio broadcaster for the World Series and All-Star Game.

Following the lead of the rival Liberty Broadcasting System, Mutual also aired regular-season Game of the Day broadcasts (a precursor to television's Game of the Week concept) to non-major-league cities throughout the 1940s and 1950s.

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