“I had the utmost respect and admiration from him based on what millions of other Americans — especially other African-Americans — thought of him from The Cosby Show,” she testified.

During a tough cross-examination later in the day, Cosby’s lawyers sought to raise questions about her credibility, pointing to what they said were conflicting statements she gave about her interactions with him.

Johnson, 55, of Atlanta, is the only one of Cosby’s more than 60 other accusers who Montgomery County Judge Steven T. O’Neill is letting prosecutors call to bolster the claim that his alleged 2004 attack on Constand followed a pattern of drugging and assaulting women.

Before the trial, Johnson had been identified in court papers only by a pseudonym, Kacey, but her lawyer, Gloria Allred, said she no longer wished to remain anonymous.

Her tearful account mirrored parts of Constand’s claim. As Cosby allegedly did with the central accuser in the case, he offered Johnson career advice and asked after her family, she told jurors. He invited her to his home and hotel. It was during a 1996 lunch date, Johnson told the jury, that he sensed she was tense and offered her a white pill.

“He wouldn’t tell me what it was,” she testified, never once making eye contact with the 79-year-old entertainer across the room. “He just kept saying, ‘Would I give you anything to hurt you? Trust me, it will help you relax.’”

Johnson said she felt pressured to say nothing after the attack, because the man was one of the biggest clients of the William Morris Agency, where she worked. Cosby later called her boss and tried to get her fired, she said.

“I heard him say: ‘She’s always away from her desk. She’s messing up her work. She’s ungrateful for all the things that have been done for her. She’s a problem. You need to get rid of the problem,’ ” Johnson testified. “I hung up the phone and I was sitting at my desk with tears streaming down my face.”

But Cosby’s defence team suggested the woman’s story did not add up. During a tense cross-examination, lawyer Brian J. McMonagle cited what he said were conflicting statements from Johnson as part of a worker’s compensation claim she filed in 1996.

Johnson cried on the witness stand and insisted she did not remember offering other or conflicting accounts.

“Did anybody tell you to get selective amnesia about this case?” McMonagle asked.

“No sir,” she replied.

During opening arguments, lawyers on both sides of the case had urged the jury of seven men and five women to set aside his fame and the media spectacle that has followed every move in the case.

“Some of you may see a brilliant comedian who made us smile,” McMonagle said during the defense’s opening statement to the panel. “Some of you may see a fallen husband, whose infidelities has made him vulnerable to these accusations. … (But) what I hope you’ll see is just a citizen, presumed innocent as he sits here.”

Prosecutor Kristen Feden, however, warned jurors not to be fooled by memories of Dr Cliff Huxtable — the charming family man character at the heart of Cosby’s most famous show. She promised to expose the 79-year-old entertainer as a manipulative predator who traded his celebrity for sex.

“You’re’ going to see the defendant for exactly who he is,” the assistant district attorney said. “This is a case about a man, who used his power and fame and his previously practised method of placing young, trusting women in an incapacitated state, so that he could sexually pleasure himself.”

Constand, a 44-year-old former operations manager for Temple University’s women’s basketball program, is expected to speak publicly for the first time about her allegations when she testifies this week.