 López's fourth title defense took place on February 23, 2008, when he defeated Jonathan Oquendo by technical knockout in the third round of an event titled "Guerra Civil".On June 7, 2008, López fought in his first world championship match when he challenged Daniel Ponce de León for the World Boxing Organization's super bantamweight title in a card organized by Home Box Office at the Boardwalk Hall in Atlantic City, New Jersey.He won by technical knockout in the first round, when the referee stopped the fight after Ponce de León failed to respond following two consecutive knockdowns.