Wednesday afternoon was absolute chaos after John claimed his son would 'bend' Paul's girlfriend, Julia Rose, over and do her 'like a dog' after their fight on December 18.
Paul was in attendance via Zoom and he looked bemused by the claim as did Tommy, who put his head in his hands in embarrassment.
BT Sport have since apologised to viewers for the language used in the broadcast.
Hearn, who is head honcho at Matchroom Boxing, has also condemned the scenes in an interview with iFL TV.
He said: "It's gonna be hard for me to not sound like a hater, but I thought it was disgusting to be honest with you. You've got the younger generation watching that...
"I mean even, actually, for one time I felt a little bit for Frank Warren [of Queensberry Promotions] because I've been there on a much less cringe stage with KSI and Logan Paul.
"Frank was embarrassed. The language is terrible. Listen, I like beef, I love it, but for me it's a bad look."
Hearn promoted a pro bout between Jake's brother Logan and fellow YouTuber KSI back in 2019 which featured more traditional trash talk.
The 42-year-old also promotes Anthony Joshua's fights, who is a big rival of Tommy's brother and WBC world champion Tyson Fury.
Hearn's understands many think his comments are because of his loyalty to Joshua, but he went on to refute those claims.
"It was disgusting, it was tasteless, the language was terrible - but me saying that it's 'Oh it's Eddie, it's just because he's not involved in the event'," Hearn continued.
"I am over the moon that I am not involved in that. Over the moon. Trust me.
"The fight's not bad, I don't mind it, but the production and everything was so bad.
"What was said, the content that was said you might say 'Oh that was great, that was great'.
"But it's a terrible look for boxing, BT knows that and Frank knows that, we know that - but it's none of my business."
Other juvenile insults were thrown in the press conference, including Paul repeatedly asking John to 'suck his d**k'.
Both fighters are undefeated going into their grudge match in Miami next month and it's incredibly personal.
Paul has regularly brought up Tommy's girlfriend, Molly-Mae Hague, and wants him to legally change his name to 'Tommy Fumbles' if he loses.
Featured Image Credit: iFL TV/YouTube & BT Sport
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