Jack Roosevelt "Jackie" Robinson (January 31, 1919 – October 24, 1972) was an American professional baseball second baseman who became the first African American to play in Major League Baseball (MLB) in the modern era. Robinson broke the baseball color line when the Brooklyn Dodgers started him at first base on April 15, 1947. The Dodgers, by signing Robinson, heralded the end of racial segregation in professional baseball that had relegated black players to the Negro leagues since the 1880s. Robinson was inducted into the Baseball Hall of Fame in 1962.

Robinson had an exceptional 10-year baseball career. He was the recipient of the inaugural MLB Rookie of the Year Award in 1947, was an All-Star for six consecutive seasons from 1949 through 1954, and won the National League Most Valuable Player Award in 1949—the first black player so honored. Robinson played in six World Series and contributed to the Dodgers' 1955 World Series championship.

In 1997, MLB "universally" retired his uniform number, 42, across all major league teams; he was the first pro athlete in any sport to be so honored. MLB also adopted a new annual tradition, "Jackie Robinson Day", for the first time on April 15, 2004, on which every player on every team wears No. 42.

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