Amber Heard served a new allegation against Johnny Depp during the ex-couple's defamation trial.

The highly-anticipated trial, which started on Monday, immediately escalated during the opening statements on Tuesday. Heard's lawyer offered a new accusation against Depp, saying that the actor "sexually assaulted" the actress before the end of their troubled marriage.

The new explosive claim, which Heard nor her team has revealed before, ultimately targeted Depp. Heard's attorneys called the incident "a three-day blackout in which he abused and sexually assaulted Amber," according to Rolling Stone.

It immediately put a twist in the defamation case that the "Pirates of the Caribbean" filed against Heard over the Washington Post op-ed she penned years ago. At that time, she claimed that she was a domestic-abuse victim but did not name Depp in any part of the article.

Meanwhile, Depp's legal team, Ben Chew and Camille Vasquez, has since pointed their fingers at the actress and claimed that she was the violent one in their marriage.

Following the new claim, a spokesperson for Depp sent a statement to CBR and Complex, debunking the allegation and called it "fictitious."

"Words are key in a defamation case and conveniently, this allegation only came after that. This follows a pattern of her elaborate, erroneous claims which have continued to change and evolve over time for the purpose of Hollywood shock value of which Amber has mastered and used to exploit a serious social movement," the representative said.

More Details About Johnny Depp, Amber Heard's Defamation Case

Elsewhere during the opening statements, Vasquez argued that the only medical report of an injury during the former couple's infamous relationship was recorded after an argument in Australia. Depp and Heard reportedly had an argument at that time, leading to the "Aquaman" star throwing a vodka bottle at him that hit his hand and severed the end of one of his fingers.

Heard's attorney, Ben Rottenborn, accused Depp and his team of trying to make the six-week-long trial into a public spectacle. He then opened up about kicking, punching, and throwing objects at Heard, giving them a warning that video and photo evidence would soon be presented during the trial.

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Vasquez then hit back and highlighted how Heard and her representatives have been lying all along.

"So, what changed? When she realized the seriousness of what she alleged [about being the victim of domestic abuse], she panicked and alleged sexual assault. In Mr. Depp's fifty-eight years, not a single woman has ever accused him of violence, and nobody in Hollywood or the world had any reason to believe he was an abuser - until Ms. Heard publicly accused him," he went on.

The defamation trial started on Monday, and it is expected to last until the end of this month.

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