Concert director Kenny Ortega broke down in tears while telling a Los Angeles court on Wednesday that pop icon Michael Jackson was "lost, cold, afraid," few days before his death in June 2009; and that his appearance at the rehearsal was "very, very troubling."

Ortega, who was helming Jackson's comeback tour 'This is It', was testifying in Jackson's wrongful death case against concert promoter AEG Live.

"I saw a Michael that frightened me, a Michael that was shivering and cold," Ortega, chocking-up with emotions, said in the courtroom as cited in the CNN report.

The concert director told the jury that he had emailed the concert promoter to warn them that "There are strong signs of paranoia, anxiety and obsessive-like behaviour."

Ortega read aloud the content of the email in the courtroom: "I think the very best thing we can do is get a top psychiatrist in to evaluate him ASAP [as soon as possible]. It's like there are two people there. One (deep inside) trying to hold on to what he was and still can be and not wanting us to quit him. The other in this weakened and troubled state."

He found the pop icon under the influence of a substance on four occasions when he had skipped the rehearsals, Ortega said. "I reached out to AEG, Michael's partners, to make sure they were aware of how I felt and what I saw."

Michael Jackson's son, Prince Jackson, 16, had testified in June, telling the court that his father was unhappy with the concert promoter. He saw his father often get upset on the phone with the CEO of AEG Live, Randy Phillips, but was unable to stand up for himself in disagreements, according to a Reuters report.

On Thursday, the pop singer's eldest nephew, Taj Jackson, 39, testified in the case. He called his late uncle his mentor. "He was definitely our mentor and everything we did in life we kind of geared toward what he was doing, whether music or how he was as a person," he told jurors.

Michael Jackson's mother, Katherine Jackson, has filed the case against AEG. She has accused the concert promoter of failing to properly investigate the pop singer's personal doctor, Conrad Murray, and ignoring signs of his deteriorating health.

AEG has denied that it hired Murray and said there was no way it could have known the doctor was giving Jackson propofol as a sleep aid, according to a BBC report.