Manny Pacquiao, Shane Mosley weigh in, with Pacquiao an 8-to-1 favorite

Reporting from Las Vegas

Manny Pacquiao’s fans swarmed, filling to capacity the draped-off MGM Grand Garden Arena on Friday to get a look at the flexed, sculpted physique of their hero.

Pacquiao satisfied the announced 8,000 fans by weighing in at a lean 145 pounds for Saturday’s welterweight title defense, even embracing his opponent Shane Mosley, who weighed the 147-pound limit.

Behind the drapes, there was more reason for Filipino pride, as Pacquiao’s trainer Freddie Roach assessed his fighter’s condition Friday after an eight-week-long effort that Roach says was Pacquiao’s best training camp ever.

“It’s all there,” Roach said backstage on the arena floor. “My true gut feeling is that we’ll win every round and the knockout should come.”

Pomona’s Mosley (46-6-1, 39 knockouts) certainly faces a difficult task at age 39. He’s coming off a convincing loss to Floyd Mayweather Jr. and a demoralizing draw against Sergio Mora last year, and now steps way up in class to try to defeat the world’s top pound-for-pound fighter.

Yes, Mosley looks fitter and livelier than he did a year ago before the Mayweather loss, and his plan to win is sound: throw a lot of his patented hard punches, make steady use of the jab and uppercuts and revert to his decade-ago ability to beat smaller men.

Easier said than done.

This is Pacquiao, capable of punching with both hands, standing on the legs of a middleweight with a proven ability to inflict relentless punishment against skilled warriors such as Oscar De La Hoya, Ricky Hatton and Erik Morales. Roach is begging Pacquiao to become the first man to knock out Mosley.

At the weigh-in, Pacquiao promoter Bob Arum told the crowd his gifted fighter is like a major league pitcher who can throw equally well with both arms. “He’s pretty damn good,” Arum said.

The pitcher doesn’t exist, but Pacquiao does. That’s why he’s an 8-to-1 favorite at the MGM Resorts’ Sports Book.

Pacquiao (52-3-2, 38 KOs) said after stepping off the scales that he plans to keep himself in the middle of the ring, jabbing, moving and going toe-to-toe with Mosley when the occasion arises.

Roach has urged Pacquiao in stronger pleas than ever to avoid his habit of leaning back against the ropes to test Mosley’s power.

“The game plan has to be followed,” Roach said.

The person who most wants a Pacquiao victory is his old rival, Juan Manuel Marquez, who was doing some backstage television analysis for ESPN Deportes, and interviewed Pacquiao after the weigh-in.

“Manny has some important work, but he is very strong. He’ll win the fight,” Marquez told The Times.

Arum is aiming for Pacquiao to next fight Nov. 12, most likely against Marquez. The pair fought to a riveting draw in 2004, with Marquez rallying from three first-round knockdowns to win 10 of the final 12 rounds. In 2008, Pacquiao beat Marquez by a disputed split-decision.

Arum has offered Marquez somewhere between $5 million and $8 million for the bout, although Marquez’s former promoter, Golden Boy, has the right to match the dollar figure, and Chief Executive Richard Schaefer said he can offer a bout against Mexico’s Saul “Canelo” Alvarez that could equal the Top Rank offer.

“If they match it, I have to respect that,” Marquez said. “But the weight — everything I want — I get. I want the Manny fight more, for personal reasons.”

He says that now. The question is whether he’ll want it as badly after where Saturday night appears to be headed.

lance.pugmire@latimes.com

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