The duo came to blows at an event promoting Mayweather's exhibition bout with Jake's brother Logan next month.
It initially started as a verbal war but quickly became physical - with YouTube star Paul ending up with a busted eye and messed up mouth.
McGregor, who has been the target of Paul's abuse in the past, has finally had his say and unloaded a vicious rant at former foe Mayweather.
"Hey @leonardellerbe [CEO of Mayweather Productions], what the f**k is Floyd at?" 'Notorious' begun.
"The kid curled up, didn't fight back once, and Floyd is still running around acting the tough guy. The kid actually just pulled this shambles of a situation Floyd is in out of the drain for him. He should thank him.
"It's embarrassing! Pro to pro it's embarrassing. He will not scratch 10m [sic] for this fight and he knows it. It was cancelled once already.
"The world is watching this on Twitter. He'd fight a half decent pro and command 20m [sic] upwards, yet its this s**t.
"Whatever way you spin this, it's sad. Fight someone for real, on your record, or f**k off mate.
UFC superstar McGregor took on 'Money' in a lucrative cross-promotion fight in 2017, which he went on to lose via knockout.
The entire scuffle started because Paul dared to steal Mayweather's hat during an intense face off.
It's currently unknown who inflicted the blows on Paul's face, with conflicting reports claiming it was either Mayweather himself or a member of his entourage.
FULL VIDEO: Floyd Mayweather and Jake Paul brawl at the Mayweather vs. Paul Press Conference at Hard Rock Stadium pic.twitter.com/9njORvYumj
- SAINT (@saint) May 6, 2021
Regardless, Paul still showed it off on Instagram in typical fashion.
He also took to Twitter with a message of: "Word on the street already is that Floyd is sending goons after me to try and kill me or hurt me. If I die....... I died for the hat."
Featured Image Credit: Conor McGregor/Instagram
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