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The baseball color line excluded players of Black African descent from Major League Baseball and its affiliated Minor Leagues until 1947 (with a few notable exceptions in the 19th century before the line was firmly established).
Before 1885 at least three African-American men played in the major leagues: William Edward White, whose light skin color allowed him pass as white, played one game for the Providence Grays in 1879; Moses Fleetwood Walker, an openly Black man who played for the Toledo Blue Stockings of the American Association between May 1 and September 4, 1884; and his brother, Weldy Walker, who played five games with the Toledo club between July 15 and August 6, 1884. Baseball officials essentially drew the color line against Fleetwood Walker. African-Americans had been excluded from major league baseball since 1884 and from white professional minor league teams since 1889. Following the 1891 season, the Ansonia Cuban Giants, a team composed of African-American players, were expelled from the Connecticut State League, the last white minor league to have a Black team.
Note:Johnny Wright was the second Black player signed to a contract by the Dodgers, and was on the roster of the 1946 Montreal Royals at the same time as Jackie Robinson, but never played in the Major Leagues.
By team
Teams are listed by franchise; i.e., teams that relocated to a new city after already breaking the color line are not listed a second time.
Expansion teams that joined the National and American Leagues after 1961 have been integrated from their first game and are not listed.
* Major League Baseball recognizes Curt Roberts as the Pirates' first Black player; however, Carlos Bernier of Puerto Rico, also a Black man, debuted on April 22, 1953.
‡ Thompson and Irvin broke in with the Giants during the same game on July 8, 1949. Thompson was the starting third baseman, and Irvin pinch hit in the eighth.