After three stints as a graduate assistant, Gilbertson became an offensive coordinator in 1977 at Utah State under head coach Bruce Snyder. After five seasons in Logan, he joined Dennis Erickson's new staff at Idaho, who immediately turned the Vandal program around in 1982, going 8–3 in the regular season and advancing to the quarterfinals of the I-AA playoffs. Shortly after, Gilbertson departed for the Los Angeles Express of the newly-formed USFL, where he coached as offensive coordinator for three spring seasons. Following the demise of the league, Gilbertson returned to Idaho in 1985, and the Vandals won their first Big Sky Conference title in fourteen years.