Manny Pacquiao says he wants to prove he is not a spent force in boxing in his world title fight against Australia's Jeff Horn in Brisbane on July 2 [July 1 in America].

Pacquiao has admitted he knows little about ex-school teacher Horn ahead of their WBO welterweight bout at what is expected to be a 55,000-strong Suncorp Stadium crowd.

The 38-year-old Filipino veteran's camp was initially reluctant to fight the unheralded Horn, preferring to set up a mega-dollar deal with former champion Amir Khan in the Middle East that fell through.

The reigning WBO champ's team say they wanted to use the Horn bout as a quick kill to "say hi to the Australian fans" before heading off and preparing for another shot at Khan.

But on Monday, Pacquiao insists the July's fight was a golden opportunity to remind fans he still had what it takes to be a world beater.

"I want to defend my crown and to prove I am still there in boxing - I am not done yet in boxing," he said.

Pacquiao - an 11-time world champion across eight weight divisions - came out of a brief retirement to defeat Jessie Vargas and claim the WBO title last November.

He is juggling his boxing career with a fulltime job as a Philippines senator but claimed the sport was still his passion.

"Despite my business in the office as a senator I am still handling my boxing career," Pacquiao said.

"Boxing is my passion. I started when I was young - it's part of my life."

Asked if he was as good as ever, Pacquiao said: "Yeah.

"It depends on how you discipline yourself, how you train and prepare yourself - it's a matter of discipline."

Pacquiao (59-6-2, 38 knockouts) is an overwhelming favourite against Horn (16-0-1 record, 11 knockouts) but is believed to have already organised a clause to have a Brisbane re-match if the Australian causes a boilover.

"I am not talking about that just yet," Pacquiao said when asked about a rematch.

"My concern right now is how to entertain the people - I know a lot of people will be watching this fight."

Pacquiao's message to 29-year-old Horn was simple.

"Work hard, show you are in 100 per cent condition on July 2 so we can entertain the people," he said.