Carlos Delgado says MLB should retire Roberto Clemente's No. 21
Rivera] League source confirms league-wide retirement of Roberto
Roberto Clemente's impact on Latin America still being celebrated
Pirates to wear No. 21 on Sept. 9 to honor Roberto Clemente
All Pirates Wearing #21, Rest of MLB Wears Patches in Honour of
Should Roberto Clemente's #21 Be Universally Retired Across MLB
It's time for Roberto Clemente's No. 21 to be retired across
Pirates Retired Numbers
MLB celebrates Roberto Clemente Day, ceremony at Citi Field