why is mlb wearing number 21

Major League Baseball players wear the number 21 to honor Roberto Clemente, a Hall of Famer and humanitarian. MLB celebrates Roberto Clemente Day on September 15 each year, during which all players, managers, coaches, and umpires wear a "21" patch on their uniforms. Players of Puerto Rican heritage, past Roberto Clemente Award recipients, and this year's nominees have the option to wear number 21 on their jerseys as a tribute. Clemente wore number 21 throughout his career, and the number was retired by the Pittsburgh Pirates in his honor. This tradition commemorates his legacy both on and off the field, including his remarkable baseball career and his humanitarian efforts before he tragically died delivering earthquake relief supplies in 1972.