George Kambosos has challenged American boxer Ryan Garcia to a street fight after the Australian suffered a loss to Ukrainian Vasiliy Lomachenko in a world title showdown in Perth.

Lomachenko controlled Sunday's bout in front of 14,147 fans from start to finish, with the fight brought to a halt with 21 seconds remaining in the 11th round after Kambosos suffered a battering in the corner.

But the drama was far from over, with superstar boxer Ryan Garcia taking to social media to say that Kambosos 'sucks'.

The remark wasn't missed by the Aussie, who fired back at Garcia, who recently tested positive to a performance-enhancing drug before his bout with Devin Haney.

'Won more belts than you'll ever win princess the clean way, cheating dog,' posted Kambosos on X. 

'I rather go out on my shield against the best and lose like a man than cheat with weight advantages and enhancements like you did. Let's have a street fight, then f*** the ring!! 

'Use all the (syringe emoji) you want.'

Garcia responded to Kambosos' attack by posting a video of the tropical destination that he is currently visiting - but this only gave 'Ferocious' more fuel.

'You should be in the Bahamas hiding away but you ain't getting away from them enhancement charges princess,' he wrote on X.

'You'll be banned from our beautiful sport that you made a mockery out of ya cheating dog. 

'I couldn't give two f**ks about you, now go stick another needle in your ass.'

Garcia then made a disgusting claim about Kambosos' wife.

'I slept with George Kambozo wife no cap,' he posted to X.

'You wanna play with me and say I did steroids. Keep playing. No mercy.

'I could show proof but then would actually be mean.

'My next goal is to make sure George wife and I are together forever and we raise his kids.

'All fair in love and war. And when George and His wife make love that's fair. But when we fight it can be war. All fair in my opinion.

'I slept with his fiancée ( George's girl ). I can beat his ass. And he can't do anything about it. I'd be pissed.

'He still hasn't came out to play.'

Kambosos was not happy about the American including his wife in their beef.

'Slept with your mother if want to get that low you dog,' he wrote.

'Shows the classless person you are talking about my wife the mother of my kids. Your dead when I see you. NO BOXING.'

Since his positive tests came to light, Garcia has been protesting his innocence on social media, insisting he has never knowingly taken performance-enhancing drugs.

It has cast a major shadow over a win that went down as the greatest of his career to date, after he floored Haney three times on his way to a majority-decision triumph.

Kambosos shot to international fame in 2021 when he won the IBF, WBA and WBO lightweight belts by stunning Teofimo Lopez at Madison Square Garden.

But back-to-back losses to Devin Haney - combined with last year's unconvincing and controversial win over Maxi Hughes - meant Sunday's fight against Lomachenko was make-or-break.

The devastating nature of the defeat raises questions about where to next for the 30-year-old Kambosos.