The Mariners Retire Ken Griffey Jr.'s Number 24, by Mariners PR
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MLB players to wear #42 Monday to honor Jackie Robinson Day
As baseball celebrates Jackie Robinson, those around the game recognize 'it's time for some progress
April 15 Major League Baseball Celebrates Jackie Robinson Day - Robert Redd Historian & Author
April 15, 1997: Ken Griffey Jr. wears number 42 to honor Jackie Robinson on 50th anniversary – Society for American Baseball Research
Ken Griffey Jr.: Road to Cooperstown by The News Tribune - Issuu
Jackie Robinson Day Museum of the City of New York
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