Juan Manuel Marquez might mix it up with Manny Pacquiao again

His face was battered, and a cut under his left eye that required eight stitches had swelled into a shiny purple welt that had grown to the size of a large grape. Still, after Saturday night’s loss to Juan Manuel Marquez in a welterweight title-elimination fight, Mike Alvarado could see a bright side.

“I give myself about a B,” said Alvarado, speaking to a small group of reporters in his locker room at the Forum. “I showed a lot of heart, and I came back when I got knocked down. ... He’s a legend, and I’m just honored to know I fought one of boxing’s legends. It was a good learning experience for me.”

For the 40-year-old Marquez, who won by unanimous decision and ran his record to 13-0 at the Forum, the fight was a career re-energizer. He has the opportunity to fight Manny Pacquiao for a fifth time — after the bout, Marquez said he hadn’t decided whether to accept that offer — with a chance to become the first Mexican fighter to win five world championships in five divisions.

“I said [Alvarado] was going to be a tough fight, and I said it was going to be a difficult fight,” Marquez said, through an interpreter. “I wanted to give the public here a gift, a gift that dignifies the history of this event and the history of the Forum.”

The judges had Marquez over Alvarado with convincing scores of 119-109, 117-109 and 117-109.

If Marquez and Pacquiao do square off in the fall, there could be a different type of fight outside the ring. How to divide the purse likely will be an issue.

The most recent time they fought, in late 2012, Marquez received a $6-million guarantee and Pacquiao was guaranteed $20 million. Marquez was 0-2-1 against the Filipino superstar at that point. However, in that fight, Marquez crumpled Pacquiao in the sixth round with a powerful right, knocking him out.

In light of that, Marquez isn’t likely to be satisfied with such a lopsided money disparity.

“It’s going to be a very difficult negotiation,” Marquez’s trainer and longtime manager Ignacio Beristain said last week of a potential fight with Pacquiao.

Asked whether Marquez is seeking a 50-50 split, Beristain said, “I don’t know. It all depends on this fight.”

Said Top Rank’s Bob Arum, who would promote the fight: “All negotiations are difficult, but we do know each other well, and our history is to find a solution.”

In the opening bout of Saturday night’s HBO telecast, Victor Postol of Ukraine knocked out Selcuk Aydin of Turkey in the 11th round of a junior-welterweight title eliminator. Postol becomes the mandatory challenger for titleholder Danny Garcia.

sam.farmer@latimes.com