Nonito Donaire Jr. and Brian Viloria, bitter rivals during their amateur days, showcase their talents when the country stages its first-ever dual world championship card on March 22 at the Araneta Coliseum in Quezon City.

Donaire, who dethroned Australia-born Armenian Vic Darchinyan by knockout, will defend his International Boxing Federation (IBF) flyweight crown against undefeated Mexican Raul Martinez in a 12-round clash.  Martinez, 27, has a 24-0 record, with 17 KOs, and is the IBA superflyweight champion.  Last November, he weighed 113 1/2 pounds in knocking out Victor Proa in one round in Philadelphia. Three years ago, Martinez tipped the scales at 119 in halting Andres Ledesma.

In the companion main event, Brian Viloria (a former WBC light flyweight champion) will take on IBF light flyweight titlist Ulises Solis of Mexico in hopes to reclaim his status as the top dog in the 108lb class - 12 round championship bout.

Promoted by Bob Arum in association with Solar Sports, the card will feature the Los Angeles-based Donaire and Viloria (grew up in Hawaii), as headliners for the first time since they fought as amateurs during the 2000 Olympic Trials.