By Rafael Soto

The open workout was held for Saturday's doubleheader at the CUM Center in Hermosillo, Mexico. In the main event, WBA/WBO flyweight world champion Juan Francisco Estrada (30-2, 22KOs), considered to be one of the best fighters in the lower weight divisions, will face Filipino contender Joebert Alvarez (14-0-1, 6KOs). WBC/WBA super bantamweight champion Jackie Nava (30-4-3, 13KOs) returns to the ring as the co-main event, against undefeated challenger Sayda Mosquera (7-0-1, 5KOs). Fernando Beltran of Zanfer Promotions is staging the show.