Some MLB Players Wearing #21, All Wearing 21 Patches Today for Roberto Clemente Day – SportsLogos.Net News
Pittsburgh Pirates, New York Mets players, coaches to all wear No. 21 on Roberto Clemente Day - ESPN
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Pirates to wear No. 21 on Sept. 9 to honor Roberto Clemente – The Denver Post
Five Astros wear No. 21 on Roberto Clemente Day
MLB allows Puerto Rican players to wear No. 21 on Roberto Clemente Day - ESPN
Somos Primos: Dedicated to Hispanic Heritage and Diversity Issues
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MLB expands list of who can wear No. 21 to honor Roberto Clemente on Sept. 15 - ESPN