Rapper and newly minted sports agent Shawn Carter, aka Jay Z, is being investigated by the Major League Baseball Players Association after giving his biggest client, Yankees infielder Robinson Cano, a watch worth a cool $33,900, according to an ESPN report.

Cano received the timepiece, a limited edition Shawn Carter Classic Fusion by Hublot, during an Oct. 22 celebration in Belgium. "Thanks to the ROC NATION my birthday gift" Cano said in an Instagram post showing the watch. He snapped another angle of the gift, revealing it to be only the second of 100 made.

Roc Nations Sports, which was unveiled in April, is a partnership with sports management giant Creative Artists Agency (CAA). During the off-season, Cano left agent Scott Boras to be the group's first big client. CAA will handle most negotiations for the player's upcoming contract, widely expected to be the most lucrative in this winter's crop of free agents. According to ESPN, Cano wants a 10-year, $310 million contract with the Yankees. The Bronx Bombers have so far offered a one-year, $14.1 million qualifying deal.

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The MLBPA rule in question states that: "No Player Agent or Applicant shall provide, cause to be provided or promise to provide, any money or any other thing of value to any player, or any person related to or associated with such player, the purpose of which is to induce or encourage such player to use or continue to use any person's or firm's services as a Player Agent, Representative, or Draft Advisor.''

Representatives are allowed to give their current clients certain types of gifts, but must disclose anything exceeding $500 to the players union. According to ESPN sources, Jay Z could be subject to disciplinary measures if the union finds he violated the regulation.

Aside from Cano, the roster for the Roc Nation sports group includes Oklahoma City Thunder star Kevin Durant and New York Jets quarterback Geno Smith, among others.