Pacquiao will challenge Matthysse for his secondary welterweight world title at Axiata Arena in Kuala Lumpur, Malaysia, on July 15 (July 14 in the United States).

Pacquiao, the former eight-division world champion and a sitting senator in the Philippines, will be fighting for the first time since last July, when he lost his welterweight world title by a tremendously controversial decision to Jeff Horn in Horn's hometown of Brisbane, Australia, in the main event of the first card of the Top Rank-ESPN long-term contract.

Pacquiao (59-7-2, 38 KOs), 39, will be boxing without Hall of Fame trainer Freddie Roach, whom he fired, for the first time in 17 years -- covering 34 fights. His head trainer is now his best friend and longtime assistant trainer Buboy Fernandez.

Matthysse (39-4, 36 KOs), 35, a big puncher from Argentina who arrived in Malaysia earlier this week, claimed a vacant secondary welterweight title on Jan. 27 with an eighth-round knockout of Thailand's obscure Tewa Kiram, after which Pacquiao sought a fight with him.