MLB's Pirates will honor Roberto Clemente by wearing his number
Pittsburgh Pirates each don No. 21 to honor Roberto Clemente - ESPN
Pirates to once again wear No. 21 for Roberto Clemente Day
Roberto Clemente day: Puerto Rican MLB players, Pirates wear No. 21
MORE
Roberto Clemente - Wikipedia
Roberto Clemente and the magic of No. 21 - MLB - ESPN
50 Years Later, the Pirates' Lineup of Color Still Resonates - The New York Times
For Many Latino Players, Roberto Clemente's Number Is Off Limits, Too - The New York Times
Demilio: Roberto Clemente Day Serves as Another Reminder to Retire No. 21
MLB Clemente Award winners wear his 21 on caps for careers
All Puerto Rican players can wear 21 on Roberto Clemente Day
