he scored a knockdown in the ninth round, López began defending the regional title, beginning an undefeated streak of six years. On June 7, 2002, he defeated Alejandro Moreno by unanimous decision, as part of a card held in Reno, Nevada. Three months later, López was paired against Alberto Ontiveros, winning by technical knockout in three rounds. On September 19, 2003, he returned to action following a year of inactivity. In this contest, López defeated Everardo Morales by unanimous decision, winning the WBO Latino flyweight championship. On December 12, 2003, he competed against Juan Alfonso Keb Baas, receiving a draw from the judges. In his first defense of the WBO Latino title, López defeated Omar Soto by knockout in two rounds. On June 25, 2004, he defended the regional title in Puerto Rico, winning against Javier Cintrón by technical knockout. This was followed by a rematch against Keb Baas, whom he defeated by technical knockout in eleven rounds. In his only fight of 2005, López won by knockout against Luis Ángel Martínez in an unification fight, which also included the World Boxing Council's FECARBOX flyweight title. On April 1, 2006, he fought against Ilido Julio for the WBC Latino flyweight championship, winning by technical knockout. This was followed by a contest versus former world champion Kermin Guardia, whom he defeated by unanimous decision in ten rounds. On December 16, 2006, López defeated the incumbent Mexican flyweight champion, Juan Alberto Rosas, by majority decision. In his only fight of 2007, he fought Antonio María Cochero Díaz, winning by unanimous decision. On April 5, 2008, López received his second regional championship opportunity in the super flyweight limit. He challenged Juan Mercedes for the WBO Latino super flyweight title, defeating him by technical knockout in four rounds. Four months later, he was paired against Oscar Andrade, receiving a technical knockout victory. The outcome was product of referee intervention after was knocked down on three occasions. On October 4, 2008, López defended the WBO Latino super flyweight title for the first time, defeating Jonathan Pérez by technical knockout in seven rounds. Winning and defending the WBO super flyweight title López became the second contender for the title held by Montiel. However, Bob Arum, Montiel's promoter, announced on January 8, 2009, that he was having difficulty to make the flyweight limit, choosing to vacate the championship. Nonito Donaire, who was scheduled to fight against Montiel,