Manny Pacquiao and Shane Mosley look for winning tactic

Reporting from Las Vegas — The planners have so much to deal with in this Manny Pacquiao-Shane Mosley welterweight world title fight Saturday.

For Pacquiao’s trainer, Freddie Roach, there’s the issue of ensuring his courageous Filipino star goes slightly against his nature to withhold some early-round daring that would expose him to Mosley’s proven power against smaller foes.

Last May, Mosley, now 39, nearly knocked down unbeaten Floyd Mayweather Jr. when Mayweather ventured inside and got clocked with some wicked Mosley rights in the second round.

“At this age, can Mosley still move for 12 rounds?” Roach said Wednesday as the fighters met with reporters at their final news conference before the pay-per-view bout that’s a sellout at MGM Grand Garden Arena.

“With a fast pace, Mosley’s legs will go. It’s going to take eight or nine rounds.”

That’s what happened against Mayweather, when Mosley grew fatigued and was defeated in a lopsided decision. He has never been knocked out.

But Mosley knows he has to conserve energy when he can, trying to break the shorter man (Pacquaio is three inches shorter) as he did routinely during his decade-ago reign as a lightweight world champion

Mosley’s cornerman, Naazim Richardson, has already proven more than capable of scripting brilliance in the ring. See Mosley’s 2009 destruction of power-hitting Antonio Margarito and Bernard Hopkins’ 2008 dismantling of then-unbeaten middleweight champion Kelly Pavlik.

“I have a solid game plan in place,” said Richardson, leery to detail it because of the reading skills of five-time trainer of the year Roach. “I have the right athlete for this.

“I’m not asking him to match Pacquiao’s speed, but to be the best Shane Mosley he can be. This is a legend, not Johnny Far Down the Road.

“It’s not just about age … it’s about Shane’s experience. Manny can come to us with all his awkward angles and speed, and we won’t fall apart. We won’t get all gladiator with him like a young guy would, going down in flames. We’ll make adjustments to what we see.”

Richardson is acutely aware of how difficult the Pacquiao challenge will be, with the World Boxing Organization welterweight champion riding a 13-fight winning streak over such names as Oscar De La Hoya, Miguel Cotto, Ricky Hatton, Antonio Margarito, Juan Manuel Marquez, Marco Antonio Barrera and Erik Morales.

“It’s a mind game, not just with Freddie, who’s as good as it gets, but with Manny, who’s not just a physical specimen. In that ring, he’s always thinking,” Richardson said.

Pomona’s Mosley still wants to employ what made him great, the “power boxing” that his father and ex-trainer Jack Mosley likens to a “jackhammer effect on cement” — keep pounding until the opponent breaks.

Roach bluntly assessed that Mosley “has trouble with speed and movement … I want Manny to use his footwork, to make him think we’re coming and we’re not, then think we’re not and we are.”

Someone asked Roach whether he expected an easy fight. “Should be,” he said.

That requires two assumptions: Mosley can’t sustain the energy he had against Margarito 28 months ago, and that Pacquiao won’t get caught engaging in his recent habit of “feeling out” the opponent’s power. Mosley has 39 knockouts in his 46 victories.

lance.pugmire@latimes.com

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