Major League Baseball circulated a directive Tuesday banning San Francisco Giants outfielder Melky Cabrera's associate from "clubhouses or all non-public areas" of all 30 major league parks.
The associate, Juan Nunez, has been alleged, according to reports, to have masterminded a failed scheme to explain away Cabrera's positive test for synthetic testosterone by fabricating a fictitious supplement and advertising it on a counterfeit website.
MLB executive vice president Rob Manfred notified teams of the action against Nunez, a consultant for Cabrera's agents at ACES Inc., in a memorandum to club presidents, chief executive officers and general managers.
Baseball has not officially confirmed reports of Nunez's involvement in the scheme. But Tuesday's memo directs clubs to ban Nunez from "non-public areas" and to avoid other dealings with him.
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. The directive then instructs teams to "not conduct contract negotiations with Nunez or otherwise deal with him regarding players on the 40-man roster."
Baseball officials uncovered the scheme as Cabrera prepared his case to challenge the test. His grievance then was dropped, and MLB announced a 50-game suspension for Cabrera on Wednesday with his team battling the rival Los Angeles Dodgers for first place in the National League West.