During the 1950s and 1960s Domingo Rivas represented Venezuela in both road and track cycling. Rivas had his first major success in 1954 when he won silver in the team road race at the Central American and Caribbean Games. Two years later he competed in both the road race and the 4,000 metres team pursuit at the 1956 Melbourne Olympics. Rivas returned to the Central American and Caribbean Games in 1959 where he won gold in the 4,000 metres team pursuit and silver in the team road race. He went on to win further medals at the Games, including gold in the team road race in 1962 and two silvers on the track in 1966.