Actor and comedian Chris Rock looked irritated and somber as he took the stand on Friday to testify in the Anthony Pellicano wiretapping case, Los Angeles Times reported.

Rock, who was admonished by the judge to "project" after muttering the spelling of his name, revealed during his 15-minute testimony that he sought the onetime private investigator Anthony Pellicano's services at the advice of his lawyer, when a pregnant woman, Monika Zsibrita, claimed she was having his child following a one-night stand, and later accused him of sexual assault.

Answering the row of questions asked by prosecutor Daniel Saunders, the comedian said he first hired Pellicano in 1999 but wasn't aware of his tactics.

"I relied on what my lawyer told me," Rock said.

Although rather bored throughout the procedure, Rock started showing annoyance signs during defense attorney Chad Hummel's cross examination.

"Someone who was not pregnant with my child, claimed to be pregnant with my child and requested large sums of money," Rock testified.

When asked about his "belief" that he was not the father, Rock heatedly replied, "That was not a belief of mine. It was true." DNA results confirmed that Rock was not the father of Zsibrita's child, so she changed her claim saying she was assaulted by the star.

Rock also told the jury that it was Pellicano who told him that Zsibrita had filed a police report claiming that he'd assaulted her. "How did you first learn about the police report of the assault," Saunders asked the comedian. "Through Mr. Pellicano," Rock replied.

Hummel asked Rock if he believed he had harmed Zsibrita in any way.

"I'm here as a free man," Rock said. "I didn't do anything wrong."

63-year-old Pellicano is accused of racketeering, fraud and conspiracy, masterminding an elaborate scheme of wiretapping, briberies to law-enforcement officials, telephone company employees and others, in order to uncover compromising information for clients preparing themselves for divorce, civil lawsuits and even criminal charges.

Rock, who admitted he hired Pellicano again two years later after the woman claimed the comedian had sexually assaulted her, was the latest in a string of Hollywood luminaries, including Paramount Pictures Chairman Brad Grey, actor Keith Carradine and comedian Garry Shandling, to appear on the witness stand in the long-awaited trial that began in early March.