Two future first ballot Hall of Famers Floyd Mayweather Jr. (left) and Manny Pacquiao.

MANILA — There’s no guarantee that if Floyd Mayweather Jr. beats Miguel Cotto on May 5 he’d call on Manny Pacquiao next.

A victory over Cotto makes Mayweather the WBA light-middleweight champion, and he may opt to move up in weight.

Roger Mayweather, trainer and uncle of the undefeated American, said part of Floyd’s agenda is to win the middleweight championship.

It should be against Sergio Martinez, the reigning WBC middleweight champion from Argentina, and it’s a fight worth watching as well.

While everybody wants Mayweather vs. Pacquiao, the reigning WBC welterweight king has already shown interest in the fight against Martinez.

“I can’t rule out the future, you know down the line I may want to make that jump and fight at middleweight, you just never know,” he told The Boxing Socialist.

“I just want to give the fans exciting fights and if Martinez is the guy at that time then we shall see, but right now my main focus is on Miguel Cotto,” Mayweather added.

Mayweather has won seven world titles in five weight divisions (super-feather, lightweight, light-welter, welterweight and light-middleweight) and is searching for another one.

The Boxing Socialist wrote that if Mayweather eventually wins the middleweight crown he can retire as the only boxer in history to rule six weight divisions without taking a single loss.

Pacquiao has won eight world titles in as many weight classes, also a first in boxing history, but has taken three losses, two of them by knockout, against 54 wins and two draws.

Mayweather stands at 42-0, and to the 35-year-old American it’s the “zero” that matters most.

To him, staying undefeated is the true measure of greatness.

Pacquiao defends his WBO welterweight crown against Timothy Bradley on June 9.

By that time, Mayweather should have regained the light-middleweight title he won against Oscar De La Hoya in 2007.

But instead of dropping down to 147 to fight Pacquiao or call on the Pinoy superstar to challenge him at 154, he might move up to middleweight and face Martinez next.

Pacquiao won’t fight any higher than 147 lb the rest of his life, and no way he’d fight Mayweather at 154, much more at 160 lb, if the latter wins the middleweight title.

Mayweather will say goodbye and leave Pacquiao behind.