Seated beside playing partner John-Patrick Smith, Hewitt savagely returned serve at Tomic, revealing the personal abuse he'd experienced at the hands of the Queenslander, which included allegations of physical threats and blackmail.
Yet Tomic has now hit back in an interview with the Herald Sun, stating: "I have never threatened his family".
"I've got nothing to do with your family and I don't care what's wrong with you, you liar".
Speaking to News Corp Australia, Tomic added: "Nice, Lleyton".
Lleyton Hewitt gave an explosive press conference on Thursday night at Melbourne Park, claiming Bernard Tomic had tried to blackmail him while sending threats to his family.
Tomic has not played Davis Cup since 2016, Hewitt's first year in charge.
Hewitt said he'd received multiple threats from Tomic.
"I don't think anyone would reach out to a person who speaks like that", Hewitt said.
"I probably took a lot for granted and I said regretful things in my own life about captains when things didn't go the way I wanted them to go". "In the end I drew a line in the sand and haven't spoken to him since".
Tomic, world ranked 88., not for years has been part of the Davis Cup team.
He was responding to Tomic's claims this week that Hewitt had ruined the national system and "no one likes him any more".
"For me, the biggest frustration is I feel like I really went out of my way to help Bernie".
However at present there were "cultural standards" not being met that were preventing any imminent return.
Kokkinakis and Kyrgios have done little to douse the flames since farewelling the Open in the first round, respectively refusing to endorse Hewitt as Australian captain and and condemning the skipper for his heavy focus on Alex de Minaur.
"The only reason I played in Austria is because we had a lot of guys unavailable". "We have a lot of issues that not a lot of players are happy about".
"For the first two years I was in this role, Bernie and Nick were my two priorities".