NORRISTOWN, Pa. (Reuters) - Andrea Constand told a packed Pennsylvania courtroom on Tuesday that she could feel Bill Cosby’s hands on her body, but the drugs in her system would not let her stop him.

“In my head, I was trying to get my hands to move, my legs to move, but I was frozen,” she testified at the entertainer’s sexual assault trial. “I wanted it to stop.”

Cosby, sitting across the courtroom, shook his head as Constand described an encounter at his Philadelphia-area home in 2004, after she accepted three blue pills that he promised would help her “relax.”

Constand is among more than 50 women who have accused Cosby of sexual assaults dating to the 1960s, often after plying them with drugs. The 13-year-old incident is the only one that is recent enough to support criminal charges.

Cosby, 79, best known for playing a revered father figure in the 1980s television hit family comedy series “The Cosby Show,” has denied all the allegations.

The outcome of his trial in the Philadelphia suburb of Norristown, Pennsylvania, largely hinges on whether jurors believe Constand’s testimony, which came on the trial’s second day.

Defense lawyers began grilling Constand on the stand late on Tuesday about several discrepancies in her initial account to police in 2005. Their questioning will continue on Wednesday.

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Constand said she first met Cosby in late 2002, when she was the newly hired director of basketball operations for Temple University’s women’s basketball program and he was a university trustee and the Philadelphia school’s most famous alumnus.

After a series of phone calls, Constand, who was then in her 30s, said the married Cosby began inviting her to dinner at his house and other events.

“He was a Temple friend, somebody I trusted, a mentor and somewhat of an older figure to me,” Constand testified.

On at least one occasion, Constand said she rebuffed his advances, telling him she had no interest.

In January 2004, Constand said, Cosby invited her to his house again to discuss her career options. That night, he offered her the three blue pills, saying they were her “friends.”

When she asked if they were herbal, he nodded, she told jurors.

Constand said she told Cosby she trusted him and swallowed the pills.

After the incident, Constand acknowledged under questioning from both sides that she maintained contact with Cosby but said she felt obligated to do so because of her job.

The defense has suggested that her repeated calls to him show the encounter was consensual.