From the season 1954/55 he started with Nordic combined. He participated in the Olympic games three times, with more and more success at the 1956 Winter Olympics in Cortina d"Ampezzo he finished sixth, and at the 1960 Winter Olympics in Squaw Valley he finished second place behind the German Georg Thoma. Three years later, Knutsen earned the Holmenkollen medal (Shared with Helmut Recknagel, Sixten Jernberg, and Sverre Stensheim).