By Ryan Burton

2016 Brazilian lightweight gold medalist Robson Conceicao (5-0) took another step forward in his pro career with a stoppage victory over Carlos Osorio (13-8-1). Conceicao dominated the action but Osorio was never seriously hurt by a punch. The fight was stopped after the third round because Osorio dislocated his right shoulder and could not continue.

Hard hitting welterweight Egidijus "Mean Machine" Kavaliauskas (18-0) kept his perfect record intact with a TKO victory over Mahonry Montes (33-7-1). Kavaliauskas came out throwing bombs from the opening bell.

The Lithuanian peppered Montes with power shots and by the end of the sixth round, Montes' right eye was completely swollen shut which prompted a visit by the doctor. He was allowed to continue but a few seconds later the referee stopped the action at the :34 second mark of the 7th round, saying that Montes could no longer defend himself. With the win Kavaliauskas captured the vacant NABF welterweight title.

2016 US Olympian Mikaela Mayer pummeled Allison Martinez in three rounds. The fight was stopped at the :39 mark of the third round. Mayer dropped Martinez a total of three times and Martinez's corner three in the towel after the third knockdown.

The opening bout saw the return of Lenny Zuppavigna (36-3) who stopped Fidel Monterossa Muñoz (38-14-1) in three rounds. The time of the stoppage was 2:48. Zuppavigna last fought in December when he lost an IBF super lightweight eliminator to Sergey Lipinets.

Next up was 2016 Uzbek Olympic gold medalist Fazliddin Gaibnazarov (3-0) who dominated Victor Rosas (9-7) from the opening bell to the final seconds of the fight. Rosas wasn't ever in real danger of getting knocked out but wasn't competitive either. The final scores were 80-72 on all three cards. 

Later on tonight WBO featherweight champion Oscar Valdez will defend his title against undefeated challenger Genesis Servania (29-0) in the ESPN televised main event. In the co-feature bout WBO super middleweight champion Gilberto Ramirez (35-0) will face Jesse Hart (22-0). The action takes place at the Convention Center in Tucson, Ariz.