Jake and Vienna: round 100.
In a new clip from Monday's Bachelor, Girardi, 24, fumes to Pavelka, who has called her out on her infidelity: "You are the biggest fake liar I've ever met in my entire life."
(Multiple sources have confirmed to Us Weekly that Girardi did, in fact, cheat on Pavelka with Greek star Gregory Michael, whose last name is bleeped out during the segment.)
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Pavelka, 32, snaps back, "Who's the guy you had on Saturday night at the apartment?"
On Good Morning America Friday, Bachelor host Chris Harrison admits the former couple's first face-to-face encounter since announcing their split "definitely got heated. It was contentious."
In another clip, Girardi, a former Hooters waitress, defends herself for selling details about their love life -- including that they hadn't had sex for months -- to a tabloid for cash.
"Either way, our relationship had been public. This was going to have to happen," she says.
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Harrison says he "doesn't buy" Girardi's explanation. "Not that I'm defending either one," he goes on. "They both have their faults. Jake felt really betrayed that she sold these very intimate stories. That's really where the interview gets heated. Jake really takes offense that he was sold out.... It was definitely a he said-she said exchange."