Photos: Jose I. Perez Cabrera/PR Best Boxing Promotions

In a sensational fight, WBA mini-flyweight world champion Giovanni Segura (25-1, 21 KOs) scored a punishing eighth round KO over previously unbeaten WBO mini-flyweight Iván Calderón (34-1-1, 6 KOs) to unify the 108lb championship on Saturday night at the Coliseo Mario “Quijote” Morales in Guaynabo, Puerto Rico. Calderon boxed beautifully early on, but Segura turned the tide and had him in trouble in rounds five and six. Calderon weathered some difficult moments, and regained his form in the seventh. Segura, however, continued to pressure the 35-year-old ring legend and floored him for the count with a devastating liver shot in round eight. Time was 1:34.

Olympian junior welterweight prospect Alex De Jesus (20-1, 13 KOs) won a six-rounder over José Ángel Román (11-26-5, 5 KOs). De Jesus was furloughed from prison for a few hours to have his first bout since March 2009.

Coming off a shock loss in his last fight, former Olympian and amateur world champion McWilliams Arroyo (4-1, 3 KOs) got back in the win column with a six round unanimous decision over Jovanne Fuentes (2-1, 1 KOs) in a flyweight bout. Scores were 60-54 on all cards.

In a battle of unbeaten lightweights, José González (12-0, 8 KOs) scored a sixth round stoppage against Héctor Marengo (5-1-4, 3 KOs). Marengo was down in round five. Referee Roberto Ramirez Jr. stopped the fight at 1:19 of round six.

Unbeaten bantamweight McJoe Aroyo (5-0, 2 KOs) took a one-sided six round unanimous decision over Sigfredo Medina (3-2, 2 KOs). Scores were 60-54 on all cards.