Knutsen started as a ski jumper, winning the national junior titles in 1949 and 1951. Whilst completing
military service, he met Nordic combined skiers
Gunder Gundersen and
Sverre Stenersen, who encouraged him to take up the event. he was the only Norwegian to win an event. He won the national titles in 1959 and 1960. It was Norway's first gold medal of the Games. Later in the year, Knutsen finished sixth at the Holmenkollen Ski Festival, In 1964, he wrote an
autobiography I hopp og løype (
In jumps and trails). ==Awards==