Trial Opens for Former Broncos CB Cox Former Denver Broncos cornerback Perrish Cox is going on trial in a sexual assault case and two Broncos players might be called as witnesses. Cox has pleaded not guilty to one count of sexual assault while the victim was physically helpless, and one count of sexual assault while the victim was incapable of determining the nature of the conduct. If convicted, he faces two years to life in prison. Jury selection begins Monday, with opening statements expected later in the week. Two players might be called as witnesses, but a witness list remains sealed and prosecutors as well as Cox's attorney, Harvey A. Steinberg, have declined to comment. An attorney for the accuser, Craig Silverman, also declined to comment. But police say wide receiver Demaryius Thomas, who caught an 80 yard touchdown pass in overtime to beat the Pittsburgh Steelers in the recent playoffs, and special teams player Cassius Vaughn were at Cox's apartment around the time of the alleged assault in September 2010. Vaughn, Cox's roommate at the time, told police he was sleeping, while Thomas said he had kissed the accuser but then left her alone when he determined she was intoxicated. Cox was at the apartment with his girlfriend, according to an arrest affidavit. The accuser came forward Oct. 28, 2010, after she learned she was pregnant. She said she didn't file a complaint sooner because she wasn't sure she had been raped and didn't want to make unfounded charges. Police arrested Cox after investigators said Cox's DNA matched a sample taken from the accuser. The affidavit said the woman was shocked when test results indicated Cox was the father. The woman told investigators that doctors put the date of conception around the time she went to Cox's apartment with friends in the early hours of Sept. 6, 2010, according to the arrest warrant affidavit. The woman said she has no recollection of most of that night and wasn't sure anyone had sex with her until she learned she was pregnant. She said she had not had consensual sex for several weeks before or after the date of conception reported by doctors. The woman said she and Cox's girlfriend at the time had gone to a club Sept. 5, and they met Cox and Thomas. When the club closed at 1:30 a.m., they all went to Cox's apartment. The woman said she believed she had been drugged because she felt unusually woozy after four drinks. Cox has repeatedly denied having sex with the accuser. He has remained free on $50,000 bail. Cox, a former Oklahoma State standout was selected in the fifth round in 2010. He started nine games as a rookie. He was cut in September by the team, which cited his performance in training camp, not the pending charges as the reason.