(ABC NEWS) -- Taylor Swift took the stand Thursday to share the details of how she says she was groped by former radio DJ David Mueller four years ago.
Swift spoke as part of the ongoing civil trial between her and Mueller, who has said that he did not inappropriately touch the pop star.
Swift told the court that at first she thought it was a mistake when Mueller reached up under her skirt, so she moved to the side, but he “didn't let go."
"He stayed latched on to my bare ass cheek as I lurched away from him," she said.
Today is the first day that Swift, 27, has taken the stand in the ongoing civil trial between her and Mueller, who has denied inappropriately touching the pop star at a 2013 meet-and-greet.
Her mother, Andrea Swift, testified Wednesday, saying on the stand that she felt "shocked" after her daughter told her that she'd been allegedly groped.
David Mueller, a former 98.5 KYGO-FM DJ, met and posed for a photo with Swift at a June 2013 backstage meet-and-greet during a Denver show.
Mueller, who also appeared in court Monday, sued Swift first in 2015, claiming that the singer had falsely accused him of grabbing her backside during the event, and that her allegation caused him to lose his job.
Swift claimed in a counter suit obtained by ABC News that Mueller "took his hand and put it up my dress" during the publicity event, and it "was not an accident, it was completely intentional."
In court filings, Mueller denied he groped Swift and "has testified unequivocally that 'I am sure that I did not.'"
Both parties are expected to cite the photo capturing the alleged incident, which was obtained by TMZ, as evidence of Mueller's guilt or innocence.
According to court documents obtained by ABC News, Mueller is accusing Swift of "intentional interference with contractual obligations" and "interference with prospective business relations" that led to lost wages.
Mueller also sued Swift for two counts of slander, but a judge threw out those claims because the statute of limitations had passed.
Swift's counter-lawsuit claims one count of assault and one count of battery, according to the documents.
While Mueller said in depositions that his damages amount to some $3 million, Swift wants compensatory, actual and punitive damages in an amount to be proven at trial, but also a verdict that holds Mueller responsible for the alleged assault.
Swift says she will donate any money she receives to charities.
Mueller is also expected to testify in the nine day civil trial.