Uniformed personnel wear No. 42 on baseball's 5th annual Jackie Robinson Day

FILE - In this July 20, 1962 file photo, baseball player Jackie Robinson embraces Branch Rickey in New York. Rickey was general manager of the Brooklyn Dodgers when Robinson was hired. The home area of the late baseball executive Rickey expects increased interest in his southern Ohio roots from his depiction in the movie “42,” in which Harrison Ford plays the man who signed Jackie Robinson to challenge baseball’s color line. (AP Photo/File) (The Associated Press)

FILE - This 1963 file photo shows Branch Rickey shown dressed for southern climates when he joined the Cardinals in Florida. The home area of the late baseball executive Rickey expects increased interest in his southern Ohio roots from his depiction in the movie “42,” in which Harrison Ford plays the man who signed Jackie Robinson to challenge baseball’s color line. (AP Photo/File) (The Associated Press)

Baseball is holding its fifth annual Jackie Robinson Day on the 66th anniversary of his breaking Major League Baseball's color barrier with the Brooklyn Dodgers.

All uniformed personnel throughout baseball were asked to wear Robinson's number 42 on Monday starting with the first game between the Tampa Bay Rays and Boston Red Sox at Fenway Park. Nine games were scheduled.

More than 100 Rays players and other club personnel saw an advance screening of the movie, "42," during spring training in Port Charlotte, Fla. The film about Robinson opened recently to a strong turnout at the box office.

Rays manager Joe Maddon said that after the spring training screening, many Rays players and coaches had a greater appreciation of Robinson's contribution to baseball.