It was what happened after the bout following one the most anticipated fights for years that got fans aching to throw a punch.

The crowd was already upset by questionable scoring which saw Floyd Mayweather beat Manny Pacquiao in the "Fight of the Century" in Las Vegas at the weekend.

And then HBO host Max Kellerman began a line of questioning that left the Filipino-born Pacquiao struggling to speak and sent social media into a spin.

Thousands took to Twitter to vent their anger at Kellerman, after he seemingly tried to persuade Pacquiao he deserved to lose.

Who was the muppet interviewing Pacman? #tool #norespect #MayPac— Mitchell Johnson (@MitchJohnson398) May 3, 2015

This just confirms why I don't watch boxing. And that #MaxKellerman dude should lose his job for that horribly opinionated interview.— Kelly Slater (@kellyslater) May 3, 2015

Disgraceful interview. Elude to your opinion If you wish but don't ram it down the throat of a guy coming off a close dec @Max_Kellerman— Evann Doumanis (@Dou_man) May 3, 2015

The post-fight interview did not go down well in the Philippines where Pacquiao is seen as a sporting hero and national treasure.

Pacquiao believed he had won and Kellerman didn't try to hide his thoughts at all.

"It's a good fight. I thought I won the fight," said Pacquiao.

"You thought you won the fight? Why?" Kellerman asked.

Mayweather claimed victory and extended his unbeaten record to 48-0 after the panel of three judges scored the fight 116-112, 116-112 and 118-110 in his favour.

The unhappiness of the crowd at the verdict was audible, making it near impossible to hear Mayweather's victory speech after the final bell.

As the jeers continued during the interview with Pacquiao, Kellerman slowed his words down in what many people said was patronising.

"But he had to be hitting you with something because you weren't attacking him with the same kind of ferocity that we sometimes see you attack. Was he not doing something to keep you off?" Kellerman asked.

"He seemed to catch you with some good right hands early in the fight. Did you feel his power?"

Then the HBO host went on: "So you're saying you thought you were up in the fight and that's why you didn't step up the pace in the 11th and 12th rounds?"

Filipino Pacquiao appeared flustered by Kellerman's  approach and the usually polite fighter appeared to lose his cool towards the end of the interview.

Kellerman told Twitter trolls he was following the best journalistic practice after his approach  elicited widespread criticism.