Pacquiao will end his fighting career against Bradley in Las Vegas

Pacquiao and Bradley squared up to each other before a raucous crowd of a few thousand fans at the MGM Grand Garden Arena on Friday for the weigh-in, with both men well within the 147-pound limit.

Pacquiao tipped the scales at 145.5 pounds, half a pound heavier than his weight for his last outing 11 months ago, his money-spinning mega-fight against Floyd Mayweather.

Bradley, 33-1-1, was a pound heavier at 146.5.

Pacquiao, 57-6-2, has made no secret of his desire to crown his career with an explosive display against Bradley, who has taken him the distance twice before.

"Expect more action that the last fights we had," said Pacquiao, who plans to concentrate on a political career in the Philippines when he retires.

Bradley meanwhile, who beat Pacquiao via a deeply controversial split decision in 2012 before losing the rematch, looked in formidable shape as he stripped down for the cameras.

The 32-year-old from California shrugged off catcalls from the largely pro-Pacquiao crowd, telling the audience: "I think there's going to be a lot of disappointed fans tomorrow night."

Pacquiao, who earned a staggering $150 million from his defeat to Mayweather last year, will bank another $20 million purse for Saturday's bout.

Although he has stated it is last fight, he has pointedly declined to definitively rule-out a return to the ring.

"I cannot say that I'm not going to come back," Pacquiao said this week, explaining that his mindset may change once he faces up to life without the sport that has made him fabulously rich and a national hero.

"I don't know how I'll feel when I hang up my gloves," he added.

Those closest to Pacquiao, including his long-time trainer Freddie Roach and the veteran promoter Bob Arum, believe he may yet return.

Arum said Pacquiao could be persuaded to prolong his career if he scores a spectacular victory over Bradley.

"I think if he wins this fight well, he's going to find a way to continue," Arum said.

Roach has been in Pacquiao's corner ever since the Filipino arrived at his Hollywood gym in 2001 looking for a trainer.

"It's been 15 years of greatness," said Roach, who hopes Pacquiao will fight on.

Pre-fight preparations were overshadowed by controversy in February when the devoutly religious Pacquiao described homosexuals as "worse than animals", remarks that prompted several sponsors to sever agreements with him while also drawing widespread outrage from gay and lesbian activists.

Pacquiao is adamant that the saga did not disrupt his training. "There were no distractions," said Pacquiao, who has expressed a desire to sign off in style.

"It's really important for me to win this fight, to win convincingly," Pacquiao said. "It's part of my legacy."

Bradley said he is preparing for an onslaught from Pacquiao.

"He's going to come out like a bat out of hell and try to take my head off," Bradley said.

Bradley teamed up with veteran trainer Teddy Atlas for his most recent bout in November, which ended in a ninth round technical knockout of Brandon Rios.

Atlas and Bradley have been poring over tapes of Pacquiao's defeat to Mayweather last year, and his crushing knockout by Juan Manuel Marquez in 2012 as they attempt to concoct a gameplan to beat the Filipino.

But Atlas is under no illusions about the scale of the challenge represented by Pacquiao.

"When you're competing against someone as good as Manny -- he wins a fight because of pure talent," Atlas said.

"The combination of speed and power that he has is uncommon. He's a freak."