Major League Baseball has issued a directive banning an associate of Melky Cabrera from "clubhouses or all non-public areas" of all 30 ballparks.

Juan Nunez, allegedly created a failed scheme to explain the Giants outfielder's positive test for synthetic testosterone by fabricating a fictitious supplement and advertising it on a counterfeit website.

The directive, according to an official of one team that received it, reminds clubs that Nunez is "not certified as a player agent" by the Major League Baseball Players Association.