In 2004, MLB established April 15 as Jackie Robinson Day because that was the day he debuted for the Dodgers and broke the league's color barrier in 1947.

For their game against the Rockies, the Dodgers are wearing script 'B' hats that resemble those once worn by the Brooklyn Dodgers. MORE: Aaron Judge, Mike Trout deliver perfect Jackie Robinson Day ...

All players, managers, coaches and umpires will wear caps with the "42" insignia ... the lone World Series the Dodgers won while in Brooklyn. Rookie of the Year in 1947, Robinson was the National ...

The Dodgers and the rest of MLB honored Jackie Robinson on the 78th anniversary of Robinson breaking baseball's color barrier ...

He recalled wearing a Brooklyn baseball cap while growing up in the neighboring borough of ... "It's not just a one-off day," Dodgers Manager Dave Roberts said. "We understand what this man did for ...