Baby Slice -- aka Kevin Ferguson Jr. -- is putting his MMA career on hold ... 'cause the fighter just signed a deal with Celebrity Boxing, the org.'s CEO tells TMZ Sports.
29-year-old Slice, 3-3 as a professional mixed martial arts fighter with Bellator, recently part with the promotion ... announcing he was transitioning to the boxing ring.
Well, that's now officially official, 'cause Damon Feldman tells us he's signed Ferguson Jr. and is in the process of finding an opponent for him.
Baby Slice will likely fight early next year.