Rilio Mastrantonio is an NFLPA-certified Contract Advisor and sports agent with Capital Sports Advisors, a multi-office athlete representation firm specializing in NFL player contracts, career management, and athlete advisory services. Based in Lynwood, Illinois, Mastrantonio has been certified by the NFL Players Association since 2012 and has been part of Capital Sports Advisors' football representation team for more than a decade. NFLPA records identify him as an active certified agent affiliated with the agency. Capital Sports Advisors was formed through the merger of several independent sports representation practices and has developed a national presence in NFL player representation. Industry reporting has identified Mastrantonio as one of the agency's key agents, working alongside veteran NFLPA-certified advisors including Thomas Mills, Cliff Brady, Kevin Robinson, Ryan Downey, and Matthew Striegel. The firm's collaborative structure enables agents to share resources, recruiting efforts, and client services across multiple regions of the United States. As a Contract Advisor, Mastrantonio assists athletes with contract negotiations, professional career planning, and representation throughout the NFL Draft process, free agency, and roster transitions. His role within Capital Sports Advisors reflects the agency's broader commitment to providing comprehensive support for professional football players and prospects.