Roc Nation is focusing on hiring experienced NFL, NBA and MLB agents, or acquiring their businesses, sources told SBJ. The company is also said to be interested in hiring soccer and tennis agents.The agency represents 11 athletes from the NBA, NFL, WNBA and MLB, most notably Kevin Durant and Robinson Cano. It announced Monday that Red Sox outfielder Yoenis Cespedes is its newest client. Roc Nation already represents Cespedes' teammate and fellow Cuban Rusney Castillo.In August, the agency hired respected boxing promoter David Itskowitch. Yormark confirmed to SBJ that Roc Nation is interested in expanding its boxing promotion business. Jay-Z, born Shawn Carter, was previously a minority owner of the Brooklyn Nets, but sold his stake in order to be allowed to represent NBA players.