DENVER — Taylor Swift took the stand Thursday, telling the court there’s no doubt in her mind she was sexually assaulted in Denver in 2013.

Swift confidently said over and over that former KYGO radio host David Mueller “grabbed my bare a**.”

Courtroom sketches showed a sharp contrast between Swift and Mueller. Swift appeared strong and determined, while Mueller was withdrawn.

Under oath, Swift said, “He had a handful of my a**. It happened to me. I know it was him. … It was a devious and sneaky attack.”

Mueller is suing Swift for being fired from KYGO after Swift’s team provided a concert meet-and-greet picture while telling Mueller’s bosses they hope the station will “do the right thing.”

Mueller said he never touched Swift inappropriately. Swift is countersuing for assault and battery.

The alleged groping occurred at the Pepsi Center in June 2013 before Swift’s concert.

“[After the incident] my eyes were on the floor, couldn’t make eye contact with either one of them,” Swift said, referring to Mueller and his then-girlfriend.

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Mueller said the photo, leaked to TMZ, captured him in movement. He said he only touched Swift’s ribs and hands.

“He didn’t touch my ribs, arm,” Swift said. “He grabbed by bare a**.”

Mueller’s lawyer pointed out the skirt Swift was wearing doesn’t look ruffled in the picture.

Swift fired back, saying ruffling in the front wouldn’t occur because “my a** is located in the back.”

Mueller’s former boss, Robert “Bob” Call, was also on the stand Thursday. He said Mueller was fired based on the photo and because Mueller had changed his story after the incident.

Mueller’s immediate supervisor, “Eddie Haskell,” also testified. He told the court he believed KYGO conducted an appropriate investigation into the accusations against Mueller.

The photographer for Swift also took the witness stand and backed up the singer’s accusations against Mueller.