Pacquiao going big, or going bust in the Battle of Brisbane

The workout was a short one for Pacquiao, who was joined by his entire team of Freddie Roach, Justine Fortune, and the brother tandem of Buboy and Haplas Fernandez in the ring. Pacquiao is favored to win over Horn but the unbeaten Australian challenger insist he will beat Pacquiao on fight night to become the new WBO welterweight champion.

"He (Horn) can derail us really badly".

"I don't think he'll beat Manny, but the thing is, he's in a very good position to help himself and help his country", he added. "I'm willing", Pacquiao said of a potential rematch with Mayweather, who has visited Roach's gym a couple of times - though not to discuss business.

"I first heard of Jeff Horn when we were offered the fight". He has to look good, he has to be impressive.

"That's why we did a lot for this training camp", Pacquiao said.

"I'm doing numbers in my head all the time on how much punishment he might be taking - how he's going mentally, how he's coping". "If there's a chance, why not?"

Asked what he would do if Horn won, Roach said: "Depending on how he lost but I would probably encourage him to retire".

"Marquez fought Pacquiao the best that anyone has fought Pacquiao".

"I don't want their judgment affected by the excitement of the fight in the heat of battle". He insists that's why he's been working hard for this.

"We are getting close to the end I know. Being there, being the underdog", he said.

"I focus on the thousands of lives I've changed - people who I've taken from depressive states and given confidence through boxing, helped them to overcome their fears, kids who might otherwise have ended up on drugs or alcohol and the parents who thank me for saving their kids".

The pinnacle would be another shot at Mayweather after the American emerged triumphant in 2015's so-called "Fight of the Century". "I've prepared for different techniques, whatever his techniques are going to be in the ring, I'm ready for that, either aggressive or moving around".

Pacquiao, 38, briefly retired previous year before making a successful comeback against Vargas in November and is juggling boxing with his duties as a senator in the Philippines.