It's a tune-up he can't afford to lose.

Waipahu-raised Brian Viloria (22-2, 13 KOs) jumps back into the boxing ring tomorrow night with a fight against Juan Javier Lagos at the Sycuan Resort & Casino in El Cajon, Calif.

The bout, to be contested at a weight limit of 113 pounds, is designed for Viloria to get some work in before fighting Ulises Solis for the IBF light flyweight title Dec. 13 in Macau, China.

Viloria already owns a unanimous decision victory over Lagos, but will fight him again in order to stay sharp heading into the December title fight.

“;Brian needs this work,”; manager Gary Gittelsohn said. “;There's no substitute for activity. I don't want (Viloria) to be inactive for what would amount to six months going into a world championship fight.”;

There is some risk in taking the fight. A loss to Lagos (15-12-2) would end any chance of fighting for a world title this year.

Viloria hasn't been world champion since losing the WBC light flyweight title to Omar Nino Romero in August 2006.

“;There's always concern about headbutts or cuts - the intangibles that you can't predict,”; Gittelsohn said. “;But it's an opponent that he should not lose too. If he did, we'd have to reexamine Brian at that point.”;

Viloria originally had a fight scheduled for August before being named the IBF's mandatory challenger for its 108-pound title. But since the bout won't take place until December, an agreement was made to allow Solis and Viloria to compete in interim fights.

Tomorrow's fight will be televised on the Latino network Azteca America.