Denver boxer Mike Alvarado may soon fight four-division champion and Mexican star Juan Manuel Marquez, with a pivotal shot at redemption on the line.

Alvarado and Marquez are negotiating contract details for a fight in May or June, according to Carl Moretti, vice president of Top Rank, who promotes Alvarado and works with Marquez.

“It’s being worked on right now for May or June,” Moretti said. “But this is nowhere near a done deal. Right now, it’s just fantasy boxing.”

The fight, if it comes to fruition, would give Alvarado (34-2) a chance to rebound from an October loss in his home state to Ruslan Provodnikov. The Russian slugger pounded Alvarado for a 10th-round TKO victory, taking Alvarado’s WBO junior welterweight title.

“If Mike beats him, then everything else is forgotten,” said Henry Delgado, Alvarado’s manager. “If he beats Marquez, then he’s back. Then we have to stay there.”

Marquez (55-7-1) is also coming off a loss. The 40-year-old lost a unanimous decision to Tim Bradley in October for the WBO welterweight title.

Marquez knocked out Manny Pacquiao in December 2012 for a stunning upset in Las Vegas, sending Pacquiao to the mat unconscious in the final seconds of the sixth round.

“If Mike can’t beat a 40-year-old guy, we don’t belong up here,” Delgado said.

The fight may take place at a catch weight between junior welterweight and welterweight, in the 144-pound range, Delgado said. And it would likely take place in Las Vegas, Delgado said.

Moretti said details are still being worked out with HBO for a television broadcast.

“It’s a fight we’re interested in. Henry and Mike would like to pursue it. (Marquez) is interested,” Moretti said.

Pacquiao and Bradley are scheduled for a WBO welterweight title fight April 12 in Las Vegas. Alvarado’s other available opponents include a rematch with Provodnikov and a rubber match against Brandon Rios.

But with Marquez, “the money is the only thing left to talk about,” Delgado said.

Alvarado has a court appearance scheduled for March on a misdemeanor driving under restraint charge. But he was not charged after an unrelated, bizarre incident involving an SUV dumped into Sloan’s Lake in January.

“Mike didn’t have anything to do with it,” Delgado said then.

Alvarado is 1-2 over his past three bouts, but only in a loss to Provodnikov did Alvarado suffer his first career knockdown. In a loss to Rios in 2012, Alvarado was stopped standing up.

Marquez earned a career-defining victory with his KO of Pacquiao, the fourth time the two rivals squared off. Marquez vacated the WBO junior welterweight title in moving up in weight for that fight — then Alvarado won the belt with his unanimous decision win over Rios last year.

Nick Groke: twitter.com/nickgroke or ngroke@denverpost.com