Citing unnamed sources, the broadcaster said the MLB Players Association is looking into whether the gift violated rules prohibiting the agents from giving money or "any other thing of value" to players.
Hip-hip artist and record producer Jay Z (real name Shawn Carter) became certified to represent NBA and MLB players this year through his Roc Nation sports group. He has since signed Cano, Oklahoma City Thunder basketball forward Kevin Durant and other high-profile athletes as clients.
Cano, a free agent, is seeking a multiyear from the Yankees reported to be worth $310 million.
Jay Z gave the limited-edition Shawn Carter Classic Fusion watch to Cano at his Oct. 22 birthday party in Belgium, the player's Instagram account indicated.
ESPN reported the MLBPA has already interviewed several of the people involved with the gift. If found to be in violation of the rules, Jay Z could be subject to "unspecified discipline," the report said.