The trial of a man accused of a beating on Main Street during the Sundance Film Festival started Wednesday morning, with the prosecutor, Paul Christensen, saying in his opening statement that the attack was “horrific.”

Christensen said John Cook, one of two men charged in the case, intentionally kicked Ryan Bilbrey during the Jan. 18 encounter. He briefly described the prosecution’s assertion that the confrontation started with Cook and another man harassing Bilbrey and his wife. Bilbrey was protecting his wife, Christensen said.

“Mr. Cook and a companion engaged, instigated, wanted a fight, and got it,” he told the jury.

But Shelden Carter, Cook’s attorney, said his side will tell otherwise. He said Bilbrey might have gone after the other person charged in the case, Kyle Erickson. Carter said there would be different opinions of the confrontation offered, and he said there would be conflicting testimony about what the people involved looked like and what they were wearing.

The trial is scheduled to run until Friday. A four-man, four-woman jury was empanelled to hear the case.

Cook faces an aggravated-assault charge. The charge carries a prison sentence of between 1 and 15 years upon conviction.

Bilbrey, witnesses to the attack, police officers and medical personnel who treated Bilbrey are expected to testify.

Carter has indicated that it might not have been Cook who attacked Bilbrey.