" By request of Commissioner Bud Selig, as Major League Baseball celebrates the 62nd anniversary of Jackie Robinson breaking its color barrier on Wednesday, all big league players and uniformed personnel have been asked to wear the late Hall of Famer's famous No. 42 on the field when the 30 teams celebrate the occasion.
The past two years, as the momentum to wear Robinson's number steamrolled through Major League clubhouses, Selig asked, but the act of wearing it was voluntary. Not so this year.
"April 15, 1947, is a day that resonates with history throughout Major League Baseball," Selig said. "With all Major League players, coaches and umpires wearing Jackie's No. 42, we hope to demonstrate the magnitude of his impact on the game of baseball. Major League Baseball will never forget the contributions that Jackie made both on and off the field."" - MLB.com