 Complete the following phrase:  A change in AIBAs rules preventing boxers under the age of 19 from competing in senior tournaments directly affected Cintrón. Despite being unable to compete internationally, he remained active in Puerto Rico and trained throughout 2013. Cintrón entered the Torneo Isaac Barrientos and won the flyweight national championship by defeating fellow Olympian Janthony Ortiz in the finals. Despite losing, Ortiz was sent to the 