Roy Jones Jr. has fought some big dudes ... but never anyone this big!
TMZ Sports has learned 53-year-old Jones Jr. will fight Robert Wilmote, AKA NDO Champ, a social media star and IFBB bodybuilding professional on January 28 in Miami.
We're told there will be five one-minute rounds.
NDO Champ (it stands for "No Days Off") is 38-years-old ... and stands 5'8". He reportedly weighs around 230 pounds.