Belliard won a silver medal with the Dominican Republic at the 1979 Pan American Games, signed with the Pittsburgh Pirates as an amateur free agent in 1980 and made his Major League debut as a pinch runner against the New York Mets on September 6, 1982. It was not until 1986 that Belliard became a regular in the Pirates' lineup, batting .233 in 117 games. He remained a versatile yet seldom used player until 1990, when he left Pittsburgh and signed a free agent contract with the Atlanta Braves.