Baseball fans have a chance to straight-up buy an autographed Babe Ruth photo that's over 100 years old ... if they got a solid $54k lying around.
TMZ Sports has learned ... a rare photo of The Bambino has been hidden in a private collection until recently ... and is being sold by Moments In Time.
In the photograph, you can see Ruth rockin' a Red Sox uniform -- when he played for them from 1914 to 1919 ... and we're told experts believe it was signed while he was a member of the Boston organization, which would make this pic 100+ years old!