Anthony Joshua furiously lashes out at fan who tells him to 'keep it professional' after fight

While AJ put on an improved performance compared with their first bout last year, he wasn't able to keep pace with Usyk at the Jeddah Superdome in Saudi Arabia and he lost via split decision.

The new footage from iFL TV shows a seemingly jovial AJ smiling and laughing with his entourage and bystanders as he walked back to his dressing room after the fight.

But the mood soon took a turn when a fan was heard shouting at the boxer, telling him to 'keep it professional'.

Joshua was filmed angrily replying: "Who are you talking to? Who the f**k are you talking to? Are you mad?”

His security team kept things moving and escorted the athlete back to his dressing room.

The clip arrives after the athlete's defeat when he delivered a passionate speech just moments after storming off stage.

"I am giving you my story," Joshua told the crowd.

"I was going to jail. I got bailed and started training my arse off, because if I got sentenced then I would not have been able to fight.

"I could have done better, but it showed the hard work he must have put in to beat me.

"Please give him a round of applause as our heavyweight champion of the world."

He continued: "I’m not a 12-round fighter. I am a new breed of heavyweight, Mike Tyson, Sonny Liston – they say, 'He doesn’t throw combinations like Rocky Marciano', because I am 18 stone, I am heavy.

"It is hard work. This guy here is a phenomenal talent. We are going to cheer for him."

Fans were just as baffled by the new clip of him lashing out at the bystander, with one writing in the comments section: "'Stay humble' while throwing 2 belts out the ring in a hissy fit."

Another said: "Put on a decent show and has utterly and completely humiliated himself after the fight."

Others, however, defended the boxer, including this person who wrote: "Everyone wanted AJ to stop being so media trained and as soon as he stops everyone get on him!"