Prosecutors are building to the conclusion of their case against comedian Bill Cosby in his sexual assault retrial.
Investigators and a pharmaceutical expert are expected to take the stand beginning Tuesday.
Cosby's chief accuser on Monday rejected a defense allegation that she manufactured her account of sexual molestation and was backed up by her mother, who said the comedian apologised and called himself a "sick man."
Andrea Constand withstood a defense cross-examination that sought to expose her as a con artist who set Cosby up, leaving the witness stand at his retrial without having budged off her allegation that he drugged and molested her at his suburban Philadelphia home in 2004.
"Did you ever fabricate a scheme to falsely accuse him for money?" Cosby lawyer Tom Mesereau asked her on Monday.
"No, sir," Constand replied.
Constand, a former Temple University women's basketball administrator, remained calm and composed throughout her testimony, which lasted more than seven hours over two days.
Her mother followed her on the witness stand on Monday and was more feisty, often clashing with prosecutors and bristling when they asked her if she benefited from Andrea Constand's $US3.4 million civil settlement with Cosby.
"She didn't buy ME a house," Gianna Constand snapped. "This isn't about money."
The mother testified about a phone conversation she said she had with Cosby about a year after the alleged assault on her daughter in which he described in graphic detail their sexual encounter and then apologised.
She told jurors that she was concerned because her daughter hadn't been the same since leaving Temple in March 2004 and moving back to Canada, screaming in her sleep and waking up in a sweat.
Gianna Constand said she was "very combative" with Cosby, demanding he tell her the medication he'd given her daughter and what he'd done to her.
She said Cosby told her he'd given Andrea Constand a prescription drug – not the cold and allergy medicine Benadryl as he has claimed – but didn't provide the name of it. She said he described how he'd touched Andrea Constand's breasts and vagina and guided her hand to his penis.
"He said to me, 'Don't worry, Mom, there was no penile penetration,"' Gianna Constand testified.
She told jurors that Cosby said he "felt like a dirty old perverted man" and, at the end of the call, conceded he was a "sick man." Her testimony prompted Cosby, sitting with his lawyers at the defense table, to open his eyes wide.
Andrea Constand told jurors last week that Cosby knocked her out with pills and then sexually assaulted her. Cosby, now 80, says Constand consented to a sexual encounter. His first trial ended with a hung jury.
At last year's trial, Cosby's lawyers suggested that Constand and the former Cosby Show star were lovers who'd been intimate with each other in the past. This time, defense lawyers are trying to portray Constand as an opportunist who feigned romantic interest in him and then leveled a false accusation of sexual assault so she could file a lawsuit.
The defense said Constand spent late nights at the comedian's home, drove four hours to see him at a casino and called him twice on Valentine's Day, about a month after the alleged assault.
Constand has testified that she saw the former TV star as a mentor and had previously rejected his advances. And she said her phone calls to Cosby were about basketball and had nothing to do with romance.
Phone records show Constand, the former director of women's basketball operations at Temple University, made brief calls to Cosby around the time of a Temple home game on February 14, 2004, the month after the alleged assault.
"You think you called Mr. Cosby to talk about basketball?" Mesereau asked her.
Constand testified that she felt a duty to answer Cosby's inquiries because he was a powerful alumnus and trustee.
The defense plans to call as a witness a former Temple administrator, Marguerite Jackson, to testify that before Constand lodged her allegations against Cosby in 2005, Constand had mused to her about setting up a "high-profile person" and filing suit. Jackson has said that she and Constand worked closely together, had been friends and had shared hotel rooms several times.
On Monday, Constand testified she didn't "recall ever having a conversation with" Jackson.
A judge blocked Jackson from testifying at last year's trial after Constand took the stand and denied knowing her. At the time, Judge Steven O'Neill ruled Jackson's testimony would be hearsay.
The judge has ruled that Jackson can take the stand at the retrial but indicated he could revisit the issue after Constand was finished testifying.
Jackson's availability as a witness for Cosby could be crucial to a defense plan to attack Constand's credibility and get jurors to believe she set Cosby up.
Prosecutors have called to the stand five other women who said Cosby drugged and assaulted them, too. The defense has called the other accusers irrelevant to the case.
If convicted, Cosby could get up to 10 years in prison on each of three charges of aggravated indecent assault.
The Associated Press does not typically identify people who say they are victims of sexual assault unless they grant permission, which Constand has done.