All Pittsburgh Pirates players and coaches will wear No. 21 against the White Sox as part of Roberto Clemente Day.
Major League Baseball has also given permission for players of Puerto Rican descent on other teams to wear the number for the day.
Even President Donald Trump sent a tweet celebrating Clemente's life.
"Today, we join millions of baseball fans and Puerto Ricans in celebrating Roberto Clemente’s life and his immense contributions to baseball and equality. He was one of my all-time favorite players – Roberto had everything!" Trump tweeted.
Today we join millions of baseball fans and Puerto Ricans in celebrating Roberto Clemente’s life and his immense contributions to baseball and equality. He was one of my all-time favorite players – Roberto had everything! #ClementeDay #Retire21 pic.twitter.com/2Hd0ePPUM9
— Donald J. Trump (@realDonaldTrump) September 9, 2020
The Pirates and the family of the late Hall of Fame right fielder are hoping to spark a movement in which No. 21 will be retired throughout Major League Baseball.
Clemente was named the National League MVP in 1966.
Tragically his life was cut short when on Dec. 31, 1972, the plane he was in crashed following takeoff in Puerto Rico while trying to take relief supplies to Nicaragua following an earthquake.
He was 38.
In 2009, MLB retired No. 42 in honor of Jackie Robinson, who broke the sport's color barrier in 1947.