This seems like something that *could* be better dealt with by teammates than by management. If Cruz, Castro, or one of the other senior players simply sat him down and said "This is not OK. You are hurting our team's chances of winning," it should be enough to make him think a little more carefully. If not, then flip him to a team that overvalues his physical skills and is willing to neglect the mistakes and flailing at balls outside the strike zone.