Today, April 15, is Jackie Robinson Day around Major League Baseball. April 15, 1947 is the day Jackie broke the color barrier, making an incredibly brave stance that all are welcome in Major League Baseball. The Cardinals participated with three main uniform changes as they wrapped their home stand.
The cap, (on the outside), was the standard home cap with the addition of a new Jackie Robinson patch on the right side of the crown. Sorry I couldn’t get a good closeup picture of the patch.
The uniforms were the standard home uniforms, but with no front numbers, and every player wore a blue 42 as their number on the back of the uniform.
The socks appeared to be solid blue on TV. I couldn’t tell if there is a subtle pattern in the sock, and I can’t find a link to these socks on Stance’s website at the moment.
Cardinals Uniforms & Logos 