Major League Baseball marks Roberto Clemente Day with ceremony at Citi Field - ESPN
For Many Latino Players, Roberto Clemente's Number Is Off Limits, Too - The New York Times
Mets honor Roberto Clemente at Citi Field
Celebrating Roberto Clemente day : r/baseball
Roberto Clemente day: Puerto Rican MLB players, Pirates wear No. 21
Pittsburgh Pirates to wear No. 21 on Roberto Clemente Day
Pirates to wear No. 21 on Sept. 9 to honour Roberto Clemente – Winnipeg Free Press
Roberto Clemente's No. 21 is 'retired in our hearts' but not on most MLB rosters - The Athletic
Demilio: Roberto Clemente Day Serves as Another Reminder to Retire No. 21
Roberto Clemente Day: Brent Suter celebrates MLB legend, wears No. 21
MLB Celebrates Roberto Clemente Day
Tampa Bay Rays honor Roberto Clemente by starting nine Latin American position players - The Boston Globe
Roberto Clemente Day: Pirates and Mets wear 21
Sources: MLB letting more players to wear No. 21 for Clemente Day
To Honor Roberto Clemente, MLB Expands List of Who Can Wear No. 21 - Sports - Remezcla