He played junior hockey for the Estevan Bruins (then a Boston Bruins farm team) and Regina Pats from 1962 to 1965. He turned pro with the San Francisco Seals in 1965-66. The depth of the Boston organization kept Gilbertson in the minors for six years. He helped the Hershey Bears win the Calder Cup in 1968-69. In September, 1977, Gilbertson suffered a career-ending car accident when he lost his lower leg. In the NHL Gilbertson played in 428 games and scored 85 goals and 89 assists. In his six NHL seasons, he only played in 3 playoff games (with Pittsburgh) and scored a goal and an assist.