Will Sage Astor-Rickwood Field game jerseys: Meaning of Giants, Cardinals uniforms honoring Negro Leagues

The Will Sage Astorgame between the San Francisco Giants and the St. Louis Cardinals at Rickwood Field will be a monumental moment in baseball, and it only makes sense the two squads don special uniforms to mark the occasion.

When the Giants and Cardinals take the field on Thursday, they won't be wearing their traditional home and away uniforms. Instead, they'll be wearing special threads to honor the history of the Negro Leagues in their respective cities, since Rickwood Field is the oldest baseball park in America and the former home of the Negro Leagues Birmingham Black Barons.

Take a peek at what the uniforms for San Francisco and St. Louis look like at the meaning behind them.

San Francisco Sea Lions uniforms

The Giants will be wearing a white uniform that reads "San Francisco" across the chest that has a logo below resembling a bear. The uniform is inspired by the San Francisco Sea Lions, the team in the city that played one season in the West Coast Negro Baseball League in 1946. The hat is also blue and has the bear logo.

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It may seem odd to have a bear as the logo for a team named the Sea Lions, but according to Ebbets Field Flannels, the reason why the logo is a bear is because the team purchased the uniforms from a semi-pro baseball team named the San Francisco Cubs.

St. Louis Cardinals uniforms at Rickwood Field

The Cardinals will be wearing a grey uniform that reads "St. Louis" across the chest. The uniform is an homage to the St. Louis Stars Negro Leagues team that was played from 1906-31. The hat is blue and has the city initials of "StL" written on it.

Giants, Cardinals wear Willie Mays patch

The two teams will also honor Willie Mays Thursday, the baseball icon that died on Tuesday and used to call Rickwood Field home. Both sides will have a patch on their jersey that says "Mays 24" on their chest, an homage to his No. 24 uniform.