The judge said the 16-year-old is guilty of forcible sexual abuse and attempted forcible sodomy, both first degree felonies, and lewdness, a misdemeanor.
The teen allegedly touched his genitals or buttocks to the faces or heads of other football players who were held down by two other team members.
The other two players pleaded guilty in December to misdemeanor counts and were ordered to perform 100 hours of community service and write letters of apology to the victims. They also agreed to testify against the other teen.
The teen found guilty today is also charged with asking two boys whom he was baby-sitting to perform sex acts on him last spring at his Salt Lake City home.
The boys, ages 8 and 11, refused to participate in the sex acts, according to court documents, which allege the defendant also held a gun to the boys' heads and told them to clean the house.
A March 7 trial has been set in the case involving the two young boys.
If convicted, the defendant faces a maximum punishment of detention at a juvenile facility until he turns 21.