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Jackie Robinson Day Celebrations for 75th Anniversary of MLB Debut
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Uniform number (Major League Baseball) - Wikipedia
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MLB players write letters to Jackie Robinson
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Boston blasts cast pall over Jackie Robinson Day
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Marlins focus on youth for Jackie Robinson Day
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Teams across MLB honor Jackie Robinson's 'eternal' impact
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MLB allows more players to wear No. 21 to honor Roberto Clemente – NBC Sports Chicago
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MLB's Puerto Rican-born players honor Roberto Clemente by wearing 21
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Angels and Mariners lock arms in show of support on Jackie Robinson Day – Orange County Register