Manny Pacquiao will need to shrug off the distractions of a deadly typhoon and a physical clash involving his trainer as he heads into a make-or-break comeback fight against Brandon Rios on Sunday.

It is almost a year since "Pac-Man" was knocked cold by Mexican arch-rival Juan Manuel Marquez, a defeat that came six months after a controversial split-decision defeat to Timothy Bradley.

A third loss in a row in the World Boxing Organization (WBO) International welterweight title clash with America's Rios on Sunday, and talk of his retirement, would amplify into a roar.

Trainer Freddie Roach has admitted that if Pacquiao loses badly to Rios, he would have no hesitation in telling him to retire.

But defeat is the last thing on the mind of Pacquiao, who has a record of 54 wins, five defeats and two draws, with 38 KOs in a professional career spanning almost 19 years.

"Brandon Rios says he's hungry to win this fight and I also say I'm hungry to win this fight because I've lost twice last year," Pacquiao said.

However, the final days of Pacquiao's build-up have been anything but smooth after Typhoon Haiyan struck the Philippines.

Pacquiao's training base in General Santos City escaped the storm but the Filipino congressman had to be talked out of interrupting his preparations to visit the disaster area.

"I'm doing my best to win this fight and give a good fight, especially with what happened to my countrymen," he said.

"To all the people and the families who have been affected by this storm, the typhoon - this fight is for you."

Pacquiao was also unimpressed by a bust-up between Roach and Rios's camp, which ended with conditioning coach Alex Ariza kicking the 53-year-old Parkinson's disease-sufferer in the chest.

As cameras rolled for a reality TV show, the two sides were heard hurling racial and homophobic insults and a torrent of expletives, while Ariza mocked Roach's slurred speech.

"Let this finish in the ring and not in trash talk before the fight," Pacquiao said.

"All I can say is this is sports. This is nothing personal, we are doing our job in the ring. Anyone who has a grievance should forgive as the Lord forgives," added the deeply religious fighter.