Horn improved his unbeaten record to 17-0-1 after the judges scored the bout 117-111, 115-113 and 115-113 in the 29-year-old’s favour, but many observers questioned the outcome, saying the officials had made a “hometown decision”.

While Horn dismissed criticism of his win, the regulatory body of professional sport in the Philippines, the Games and Amusement Board (GAB), requested a “thorough review” of the fight on Monday and Pacquiao has backed their demand.

“WBO should take appropriate action on the letter sent by the Games and Amusement Board (GAB) so as not to erode the people’s interest in boxing,” eight-division world champion Pacquiao said in a statement on Wednesday.

“On my part, I had already accepted the decision, but as a leader and, at the same time, fighter, I have the moral obligation to uphold sportsmanship, truth and fairness in the eyes of the public.”

“I love boxing and I don’t want to see it dying because of (an) unfair decision and officiating.”

On Tuesday, the WBO said that the decision could not be reversed and highlighted the rematch clause in both fighters’ contracts.

“The discretion of a referee or judge cannot be reversed, except in a case of fraud or violation of laws which is not the case in Pac vs. Horn,” the organisation said on their Twitter account.

“The contract for Pac vs. Horn provides a rematch clause, which the WBO is in accordance if the promoters decide to move forward.”

The 29-year-old former schoolteacher was awarded a unanimous 12-round decision over the eight-division world champion, after a bloody battle in front of more than 51,000 fans at Brisbane’s Lang Park on Sunday.

Not everybody was happy with the victory, awarded with scores of 117-111, 115-113 and 115-113 by the three judges, and former undisputed world heavyweight champion Lennox Lewis was among those who disputed whether Horn should have won.

“There’s always going to be the backlash where people are going to say I am lucky, or whatever,” Horn, his right eye swollen shut, told reporters in Brisbane on Monday.

“There’s always naysayers, saying I didn’t win the fight.

“I think I won the fight, a lot of Queenslanders think I won the fight and people around the world. So you will always have the select few that are against you.”

The critics of the decision pointed to the 182 to 92 punch count in favor of the Pacquiao, with some suggesting that Horn was awarded the victory for effort.

“This is what’s wrong with boxing,” Lewis tweeted.” Horn was a very game but I’m hard pressed to see how he could have won that fight by any stretch!”

Pacquiao, whose defeat was his first since his blockbuster clash with Floyd Mayweather Jr in 2015, indicated on Sunday that he would take up the option of a rematch.

And Horn said he would be delighted to face the 38-year-old in his first title defence.

“I’m happy to have a rematch. It’d be good to have him back here fighting,” he added.

“Manny Pacquiao is an absolute warrior, he’s a legend of this sport. He might have come in underdone, if we have a rematch, if he puts it all in, I don’t know…”

Horn, whose career record improved to 17-0-1, said he would also like to have a crack at 40-year-old Mayweather, who has come out of retirement for a 12-round crossover bout against mixed martial arts champion Conor McGregor.

“I hope so,” Horn said. “I’m world champ now. And he has been out of action and coming back to have a fight with Conor McGregor.

It will be a good test for him to cement his record in history to fight another boxer for his title.”

Horn, whose meeting with Pacquiao shattered the Australian attendance record for a fight, said he would prefer to defend his title on home soil and was hoping for a bit more recognition ahead of his next bout.

“It was, I guess, the Manny Show,” he said of Sunday’s fight.

“Even on TV, I can remember watching programmes saying the Manny Pacquiao fight in Brisbane.

“My name wasn’t normally mentioned in those programmes, but now hopefully I’m a bit more recognised and I’ve established myself in the boxing community a bit more.”

Horn said he was prepared for the media attention becoming a world champion would bring and hoped his victory would trigger a renaissance in Australian boxing.

“It puts Australian boxing on the map, it’s what we’ve needed for a long time, it’s kind of died a bit in the past but hopefully this will invigorate it,” he said.