The teenage boy who has accused Michael Jackson of sex abuse has admitted telling a former teacher he had never been molested by the US singer.
Michael Jackson was taken to hospital with back pain last week
Fifteen-year-old Gavin Arvizo returned to the stand for cross-examination by Mr Jackson's lawyers on Monday.
Last week the court in Santa Maria, California, heard the boy's account of how the alleged abuse took place.
The singer, who denies all charges, was in court for the first time since his late arrival last week with back pain.
During intensive cross-examination by Mr Jackson's lead lawyer, Thomas Mesereau, Gavin conceded he had told a former teacher that nothing inappropriate had happened between him and the singer.
Apparently reading from a transcript of the interview, Mr Mesereau quoted the teacher, Jeffrey Alpert, as saying: "Look at me, look at me... I can't help you unless you tell me the truth - did any of this happen?"
Mr Jackson's Neverland ranch is at the centre of the case
Gavin acknowledged from the witness stand his answer at the time - apparently just after a 2003 documentary which sparked the investigation into Mr Jackson - had been "no".
"I told Mr Alpert he [Michael Jackson] didn't do anything to me," the teenager said.
Mr Mesereau drew attention to numerous disciplinary problems the teenager had had at John Burroughs Middle School, where Mr Alpert was the dean.
Gavin admitted he had been disruptive, rarely did homework and regularly argued with his teachers.
The BBC's Daniella Relph in Santa Maria said: "The exchanges between Gavin Arvizo and the lawyer Thomas Mesereau have been some of the most aggressive during this trial.
"The judge has even told both of them not to be so argumentative. But the assertive cross-examination has shown up inconsistencies in the teenager's story."
Mr Jackson arrived 15 minutes early for proceedings on Monday, wearing a red coat with a black arm band.
On Thursday, the singer triggered a threat of arrest by the judge when he arrived late, wearing pyjamas and slippers.
In a statement, Mr Jackson's defence said he had been taken to a hospital for treatment for a severe back problem after tripping and falling over while getting dressed.
Later on Thursday, Gavin Arvizo described how the alleged abuse took place in the singer's bedroom at his Neverland ranch in 2003.
The teenager said he and Mr Jackson were in bed together and that, after asking the boy lots of questions about sex, Mr Jackson had put his hand down Gavin's pyjama bottoms and touched him.
He also described consuming various kinds of alcoholic drinks - including vodka, wine and brandy - with the star.
On Friday, the court heard legal arguments in which prosecutors sought access to Mr Jackson's financial records, claiming he has debts of $300m (£156m) and faces liabilities of $400m (£208m) by the end of the year.
Mr Jackson denies 10 charges including child abuse and false imprisonment. If found guilty, he could face a 21-year prison sentence.