The Dominican national volleyball team defeated Puerto Rico yesterday in the first of two games that are being played to determine which of the two islands will represent the region in the World Volleyball Games scheduled for Japan in November. The first of the matches was held in Guaynabo, Puerto Rico. The Dominican team is scheduled to play Puerto Rico again Saturday at the Volleyball Pavilion of the Juan Pablo Duarte Olympic Center in Santo Domingo. The Dominicans defeated Puerto Rico 3-0. The games ended 15-12, 15-8 and 15-8. Cuban technician Jorge Pérez Vento is the coach of the Dominican team.