The Canadian junior leagues were smacking their lips in anticipation of getting Sheehy on their roster, but Sheehy took the unconventional route at the time by bypassing the major junior leagues in order to get an education. He would enroll with Boston College in 1966. Back then it was rare to see a top hockey prospect play college hockey as the juniors were considered to be one step away from the NHL. Sheehy was a star at BC as well. He scored 185 points in 80 games and was an all-American in 1969 and 1970.
While Sheehy had become a hockey legend back home in International Falls and on the campus of Boston College, it wasn't until the 1969 World Championships that he began to make a bigger name for himself. He was invited to play for Team USA in the Worlds. He thoroughly enjoyed the experience. He returned to Boston College for the 1969-70 season to finish his education, but returned to the national team program in 1970. He played the next two seasons with the United States national team and before long was perhaps the team's best player. He was named captain of the squad prior to the 1972 Winter Olympics in Sapporo Japan. Team USA shocked the world with a surprising silver medal. Sheehy was instrumental in that team's success, scoring 4 goals and 5 points in 6 games.
Following the Olympics Sheehy made the big jump to the professional ranks. Never drafted by an NHL team, he decided to skip the NHL and return to the New England area where he signed as a free agent with the New England Whalers. He played 3 seasons there before being moved to Edmonton and later the Birmingham Bulls.
The Bulls held on to Sheehy for just 50 games before trading him with Vaclav Nedomansky to the NHL's Detroit Red Wings for Steve Durbano and Dave Hanson. The Wings however quickly gave up on him. He played in 15 games with the Wings but his only significant stat was his -13 (he scored no points). The Wings sent him to their minor league affiliate in Kansas City where he continued to struggled.
Sheehy was rescued by his old team the New England Whalers. They bought back his rights from Detroit and Sheehy returned to the Whalers.
When the Whalers merged with the NHL in 1979, Sheehy participated in 12 more NHL games, scoring 2 goals and 1 assist. However he spent most of what proved to be his final season in the minor leagues.
Sheehy is a legend when it comes Minnesota high school hockey, Boston College hockey and Team USA. Sheehy was a good player at the WHA level, scoring 173 career goals and 344 career points in 420 WHA games. Sheehy was never able to do much at the NHL level. It would have been interesting to see him play in the NHL at an earlier age.