The 41-year-old American returned from a two-year retirement last year to face UFC star Conor McGregor in a big-money fight contested under Marquis of Queensberry rules.
Pacquiao, 39, bounced back from his decision loss to Australian Jeff Horn last year to stop Lucas Matthysse in seven rounds last July.
The Filipino superstar is holding out hope that he can entice Mayweather back into the ring.
“It will be different this time as there will be no excuses,” Pacquiao told Mirror Sport. “I can’t retire with peace of mind because of the defeat. If you watch the fight, he didn’t throw many punches.”
It was recently revealed that Pacquiao had signed a deal with high-profile advisor Al Haymon, who also works with Mayweather.
Before the rematch can happen, Pacquiao must first get past former titleholder Adrien Broner when the pair meet early in the new year.
“I will have a couple more fights left in boxing,” said Pacquiao, who is also a senator in his native Philippines. “First I am fighting Broner and after that there is a big possibility of the Mayweather fight.
“He is coming back and we are talking about a rematch but we have to deal with these fights first.
“We met in Japan and he said he wanted to have a rematch; not this time but maybe after the January fight.
“I told him I have the belt and that I am the champion.”