Ríos, Hernández to wear uniform No. 21 on Roberto Clemente Day
Pirates will honour Roberto Clemente by wearing his No. 21 on
Puerto Rican players follow Pirates' push to wear No. 21
Entire Pirates team will wear No. 21 to honor Roberto Clemente
Carlos Delgado says MLB should retire Roberto Clemente's No. 21
Roberto Clemente - Wikipedia
For the 'Great One'; Pirates, MLB honor Roberto Clemente
Demilio: Roberto Clemente Day Serves as Another Reminder to Retire
All Puerto Rican players can wear 21 on Clemente Day
MLB Celebrates Roberto Clemente Day