Rivera doesn't strike me as the kind of guy who'll hang on to a player who doesn't want to be here just to "prove his manhood". He seems like more of a "you're not part of the program, so get lost" type.
If he wants out, trade him...dont need the drama. If he wants to stay and work keep him. /story
We don't really know what his impression of Smith is, but if it's a bad one I don't think he'd hesitate.