LAS VEGAS -  Manny Pacquiao’s fight with Sugar Shane Mosley is a good one day away from happening, but the pound-for-pound king is already booked for another bout before the year ends.

Top Rank Promotions already reserved a Nov. 12 schedule for the Filipino southpaw at the MGM Grand here in what possibly could be the final installment of the Pacquiao-Juan Manuel Marquez trilogy.

Veteran promoter Bob Arum, the brain behind the Top Rank outfit, said he’s laying his eyes on the 37-year-old crafty Mexican as Pacquiao’s next opponent six months from now, provided the welterweight title holder beats Mosley.

“It’s Nov. 12 I hope to do the fight here at MGM,” Arum disclosed. “And Juan Manuel Marquez is my first choice.”

But Sugar pulling off a monumental upset against the Pacman would shelve the long-awaited third meeting between the eight-time world champion and his old nemesis from Mexico City.

“We have a rematch clause (in case Mosley wins) and it takes place within six months,” Arum added.

If not, then Marquez gets his final crack at finally getting even against the man responsible for the two blots in his Hall of Fame career.

“Now if Marquez is not available, then we’ll be looking at Timothy Bradley or the other younger guys out there,” said Arum.

Bradley is the reigning World Boxing Council (WBC) and World Boxing Organization (WBO) light-welterweight champion.

Pacquiao himself said during Wednesday’s final press conference for the Mosley fight that there is a big possibility of facing Marquez next, even saying chances of it finally happening is within 80 percent.

As for what weight class, Pacquiao answered, “I don’t know yet.”

Marquez has yet to sign a new contract with old promoter Golden Boy since his previous deal expired last February, but the promotional outfit owned by Oscar De La Hoya owns the right to match any offer to be given by other firms to the durable Mexican.