The year 2019 will prove to be a definitive one in the career of Anthony Joshua.

Back in June, the British fighter succumbed to his first defeat as a professional, with Andy Ruiz Jr stunning the sporting world in Madison Square Garden.

The Mexican won thanks to a seventh-round TKO, knocking Joshua down on four separate occasions during the fight.

It was one of boxing's biggest ever upsets, but Joshua will have a chance for redemption in the rematch on December 7 in Saudi Arabia.

If AJ can banish his demons and secure victory over Ruiz, the boxing world will once again be his oyster. Lose and there's a chance his career could fall apart.

Many former and current boxers have been very vocal on Joshua's predicament, none more so than former heavyweight champion Lennox Lewis.

After the Ruiz fight, Lewis criticised his fellow countryman's preparation for the fight on social media and stated that he should part with his trainer, Rob McCracken.

But Joshua has now fired back at a man many thought he respected.

"Lennox is a clown. I don't respect Lennox," Joshua said on AJ: The Untold Truth, per Boxing Scene.

"Me and Lennox are not the same. My legacy is to sit back and enjoy the younger generation coming up, and not to be involved. Just to appreciate what it takes to get there. Lennox isn't like that. Me and Lennox are cut from a different cloth."

When asked about Lewis leaving an impressive legacy on the sport, Joshua snapped back: "So? So am I."

The 29-year-old has finally snapped and who can blame him?

While criticism is expected, the severity of it from all corners of the globe has been pretty ridiculous.

After all, Joshua was facing one of the top 10 heavyweights in the world during that difficult evening in New York City.

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