Mikey Garcia is in "good spirits" after that crushing loss to Errol Spence over the weekend ... but that doesn't mean he's looking to do it again any time soon.
We spoke with Mikey's brother, Robert Garcia -- who also trains the boxing star -- and he told us everyone is still sad for Mikey because they were expecting a legacy-defining victory.
Obviously, that's not what happened ... Mikey lost nearly every round to Spence -- who proved to be the superior fighter in just about every way.