Lupe Pintor was born into a poor, working-class family in Cuajimalpa, just outside Mexico City in 1955 and is alleged to have had an extremely violent relationship with his father, eventually forcing him to run away.
He opened his account with a second-round knockout of Manuel Vázquez and immediately stepped up to ten round bouts, claiming a decision over Francisco Nunez on his next outing.
He suffered his first loss three fights later, when he was disqualified against Magarito Lozano, but claimed victory in his next eight bouts, seven by knockout, including wins over notables Juan Díaz, Rocky Mijares and Willie Jespen.
Pintor first boxed future World Bantamweight Champion Alberto Davila on 25 February 1976, losing a decision over ten rounds, then embarked on a winning streak of some twenty-two fights in a row.
Amongst the fighters he beat during this period were Gerald Hayes – who later conquered Juan Laporte – and Antonio Becerra, the only man to get the better of Salvador Sánchez as a professional boxer.
Then he began to defend his title in earnest, retaining it with a knockout in twelve over Alberto Sandoval in Los Angeles and drawing over fifteen with Eijiro Murata in Tokyo.
Saddened, Pintor – encouraged by Owen's family – resumed his career by avenging his loss to Davila, retaining the title by unanimous decision.
Soon after the Lee fight, Pintor vacated his world title and started eyeing the WBC Super Bantamweight crown worn by the great Wilfredo Gómez.
Traveling to Bangkok to meet Samart Payakaroon, Pintor exceeded the division weight limit and was subsequently stripped of his title at the scales.
Pintor, along with Hector Camacho, Hilario Zapata, and several non-boxers, was voted into the International Boxing Hall of Fame in December 2015 and inducted in June 2016.