The World Boxing Council on Monday declared US fighter Oscar de la Hoya the new welterweight champion of the world after reigning champion Felix Trinidad, of Puerto Rico, renounced the title.
Trinidad is moving to a higher weight category.
De la Hoya, 32-1 with 26 career knockouts, will defend the title against Shane Mosley, who is now the official challenger in the welterweight category, the WBC announced in a news release.
Trinidad announced on Sunday in Puerto Rico that he would give up the title and continue his career in the super welterweight category.
Trinidad is the super welterweight champion of the World Boxing Association, a title he won last month against US fighter David Reid.
The WBC sent a representative to Los Angeles to officially present the world champion belt to de La Hoya in a special ceremony.
Trinidad, undefeated in 37 fights, delivered De la Hoya's only defeat in a fight for the welterweight title on September 18, 1999, winning a controversial split decision.