Born in Bolívar, Colombia, Rodrigo Valdez began his professional boxing career with a win over Orlando Pineda in a four-round decision on October 25, 1963, at Cartagena.

He won his next eight bouts, but on October 2, 1965, he lost his undefeated record, beaten by knockout in six by Rudy Escobar.

In his next match, held at the Madison Square Garden in New York City, with Bobby Cassidy on August 9, 1971, Valdez won by knockout in round six, because the fight doctor deemed Cassidy not fit to continue from a cut around his eye which had been ruled as produced by a Valdez punch.

One week before the long-awaited match-up, on June 19, 1976, Valdez's brother was murdered during a barroom fight in Colombia.

Valdez was leading after seven rounds, but Monzon mounted a late rally that allowed him to keep the title by a close decision.

Monzon announced his retirement from boxing afterwards, and so Valdez and Briscoe were matched once again, on November 5, 1977, for the vacant undisputed world middleweight championship, in Campione d'Italia, which belonged back then not to Italy, but actually to Switzerland.

This time around, however, he would lose his title on his first defense, on April 22, 1978, by points in 15 rounds to another Argentine, Hugo Corro, in San Remo, Italy.

On November 11 of that same year, they had a rematch, at Buenos Aires' Luna Park Stadium, and Corro repeated his 15-round victory to retain the world title.