Amber Heard has been accused of "inventing" a rumour that Johnny Depp pushed his ex-girlfriend Kate Moss "down the stairs" into his libel trial in a "moment of unscripted malevolence".
Depp, 57, is suing News Group Newspapers for libel over a story published in The Sun in 2018 which branded him a "wife beater" - an allegation he vehemently denies.
The trial has reached day 16 and is expected to come to an end this afternoon.
Depp has denied ever being violent towards his ex-wife, and claimed it was Heard who was abusive towards him throughout their relationship.
The actor's lawyer, David Sherborne, began his closing statements and addressed the moment Heard dropped a bombshell claim about Depp's supermodel ex during her testimony.
He alleged she deliberately threw the "rumour" into her testimony out of spite.
Sherborne said Heard "in yet another moment of unscripted malevolence" had "tossed in a detail" to say she had "remembered a rumour" that Depp had pushed Moss down the stairs.
He told the court Heard had never mentioned the "rumour" in any of her seven witness statements to the court or in statements for any other proceedings.
Sherborne said Heard "blatantly invented" the Kate Moss story. It showed Heard's "evidence just cannot be relied upon".
Heard made the claim while she was giving evidence last week.
It came when the actress spoke about a row between the couple at their Los Angeles home in March 2015 when her sister Whitney was present.
Heard claimed she struck Depp to protect her sister as the row was taking place in between two flights of stairs - and she added a "rumour" she'd heard about Moss.
Heard said: "I heard the rumour he pushed an ex-girlfriend down the stairs - I think it was Kate Moss - and that was fresh in my mind... So I reacted quickly.
"I have been Johnny's punching bag for years... And I remember this as it was the first incident when I ever struck him back."
Depp dated Moss from 1994 until 1998. He has yet to comment on the "rumour" Heard referenced in court.
Moss has previously spoken warmly about her romance with Depp, and admitted he took care of her ad she cried for years after their split.
She told vanity Fair magazine: "There's nobody that’s ever really been able to take care of me.
"Johnny did for a bit. I believed what he said. Like if I said, ‘What do I do?,’ he’d tell me.
"And that’s what I missed when I left. I really lost that gauge of somebody I could trust. Nightmare. Years and years of crying. Oh, the tears!"
During the trial Depp denied he'd ever been violent towards his ex-wife and claimed she'd been abusive towards him during their relationship.
Lawyers for NGN are defending their case based on Heard's 14 allegations of abuse, which include claims of bust-ups between 2013 and 2016.
Depp denies all her allegations.