LAS VEGAS — Manny Pacquiao blew into fight town Monday greeted by the tall odds.

At 46 and four years removed from his last fight, Pacquiao understood why it was so.

“We’ve been retired for four years, so that’s okay,” said Pacquiao, who challenges the youthful and energetic champion Mario Barrios for the World Boxing Council (WBC) welterweight crown this Saturday at the MGM Grand.

But Pacquiao insists he will be answering the bell with fresh legs since he had apparently gotten rid of the troubling leg cramps that had been pestering him since his first meeting with Juan Manuel Marquez of Mexico in May 2004.

“It’s sad that I only discovered why I had been suffering from it only in this training camp,” said Pacquiao, who arrived here after a horrendous seven-hour and 45-minute ride from Hollywood that was caused by a fire in the town of Baker and massive road repairs leading to Sin City.

The Filipino eight-division legend told Manila-based scribes that he experimented on it by not allowing his legs to be massaged daily.

“In the past, I would get massages, sometimes twice a day. So, in this camp, I tried resting it and the result was great because I haven’t experienced cramps since then.”

The MGM Grand betting station lists Pacquiao as +225 ($100 wins $225) and Barrios -300 $300 wins $100).

In the round betting, the betting sheet lists Pacquiao as 100/1 for a first-round victory and 6/1 to win by decision and 5/1 to win by knockout or disqualification.

Barrios, younger by 16 years, will be making the second defense of the WBC 147-pound belt that he has vowed to keep no matter what.

He is listed as 2/1 to win on points and +120 ($100 wins $120) to win by knockout or disqualification.

Pacquiao, whose last fight was a decision defeat to Yordenis Ugas of Cuba at the T-Mobile Arena, arrived here accompanied by wife Jinkee and their children.

He spent training camp in Los Angeles where Buboy Fernandez assumed the role of lead trainer and Marvin Somodio acting as assistant, Justin Fortune as strength coach and Freddie Roach as consultant and adviser.

Having gotten rid of an old issue, Pacquiao expects to come out swinging and eventually triumphant in this bold bid to pull off another major achievement.