He bought the Philadelphia Blazers of the WHA and promptly moved them to Vancouver in 1973. After two years it was clear that the Blazers were losing to the Vancouver Canucks so Pattison moved the Blazers to become the Calgary Cowboys.
However the 6500 seat Stampede Corral was not big enough to support a big-league team. After two years of trying to convince the city to expand the Corral, Pattison had to fold the Cowboys. It was not until the Atlanta Flames moved to Calgary in 1980 and the city was awarded the 1988 Olympics that Calgary got a big-league facility (Olympic Saddledome).