1 legendary Met is out, another is in ... 'cause Dwight "Doc" Gooden will referee the "Bagel Guy" vs. Dustin Diamond celebrity boxing match this weekend.
Promoter Damon Feldman tells TMZ Sports he struck a deal with Gooden ... who will be inside the ring reffing Saturday night at the Showboat Casino in Atlantic City.
Remember, the fight was originally supposed to be "Bagel Guy" Chris Morgan against NYM great Lenny Dykstra .