Although he had multiple scholarship offers for college football, including Pac-8 schools, he decided to stay in state and attended the University of Idaho in Moscow. He was a defensive lineman for the Vandals and was ticketed to redshirt in 1976, but was called into action in the fourth game of his sophomore season. The Vandals went 7–4 in 1976, their first winning season in five years, and were 5–2 in the seven games that Fagerbakke started. Head coach Ed Troxel planned on moving him to the offensive line in 1977, but a knee injury in spring drills ended Fagerbakke's athletic career, which turned his focus to theater. (The Vandals went 3–8 in 1977 and Troxel was fired; then 2–9 in 1978 under Jerry Davitch, one of the wins being a "no-show" forfeit.)