Mikaela Mayer predicted the performance of her life, while Alycia Baumgardner vowed to shut her opponent up, before the pair once again needed to be split by security in their face-off ahead of Saturday's Fight of the Night contender at The O2.
The American rivals had clashed during a media recording the day before when Baumgardner suggested she had lacked the same "resources" as Mayer throughout their early boxing careers.
Mayer sought to quash that narrative in response and at Thursday's press conference highlighted her success as the reason for her opponent's dislike towards her amid their fiery feud.
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"She doesn't have much to lose, she just showed up on the scene," said Mayer. "If she goes somewhere nobody is going to miss her.
"I've got a lot to prove because I've been running this division for a long time, that's why she's so mad at me. I'm not just talking about the pros, I'm talking about the amateurs.
"She's known my name and has been coming for my name for a long time. I've worked extremely hard to get to this position and I'm not going to let her take that away from me."
Baumgardner insisted she has no respect for Mayer while suggesting her standout win over Terri Harper "was just a fraction of who I am".
"There's a difference, my confidence is triggered by her," added Baumgardner. "Every one of her fighters she has fought has come to fight her and go back home.
"She now has a fighter in front of her who is willing to fight her and telling her how it is, that I'm going to beat her, that I will break her jaw. Whatever it is, I'm in her face and she does not like it.
"This is confidence we're dealing with. I'm a competitor at heart, I've been doing this since I was eight and I'm excited."
Baumgardner has been critical of Mayer throughout the extensive build-up to their super-featherweight unification bout, citing a supposed lack of progression on her opponent's part.
"She said a lot of things, boring, flat-footed, look the same of the amateurs, to me that just shows her ring IQ," responded Mayer. "I know I’m constantly improving, when I go into camps with my coaches we’re constantly trying to get better, her ring IQ obviously isn’t as high as she says it is.
"I’m expecting the performance of my life. Contrary to what she’s saying that I haven't developed, it isn’t true. I still feel like I haven’t hit my peak.
"I want to embarrass her and make her sound stupid. Whether she likes me or not, on paper I am her absolute biggest test. I’m a multiple time world champion, Olympian, she hasn’t fought anyone with my resume. She has to accept that."
Baumgardner preceded to suggest the knowledge she is going to lose was "a tough pill to swallow" for Mayer.
"That's great, all those attributes, but it doesn't matter come Saturday night because a fighter like me will beat that and that will be embarrassing on her record that somebody that came out of the woodwork that became a world champion, doesn't have the experience, is going to beat her, that's great," she continued.
"When somebody talks too much you've got to shut them up. On Saturday night."