Why are MLB players wearing No. 42 jerseys today?

Jackie Robinson's 42 in Dodger blue for all uniforms on April 15 - Washington Times

All MLB Teams Wearing No. 42 In Dodger Blue On Jackie Robinson Day

Jackie Robinson Mitchell & Ness Nostalgia Co.

MLB celebrates timely Jackie Robinson Day

Cincinnati Reds on X: Let's take a look at the 2018 holiday and special event #RedsThreads! We'll start with Jackie Robinson Day on April 15 vs. STL, the 71st anniversary of Robinson

Last player to wear No. 42 for each MLB team

Angels and Mariners lock arms in show of support on Jackie Robinson Day – Orange County Register

A's, Astros walk off field in protest, game postponed

Baseball Celebrates Clemente with “21” Patches; Pirates and Award Winners All Wearing #21 – SportsLogos.Net News