North American Soccer League is former a soccer league in United States and Canada . North American Soccer League ( NASL ) was a professional soccer league with teams in the United States and Canada that operated from 1968 to 1984 . In 1967 two professional soccer leagues started in the United States : the FIFA-sanctioned United Soccer Association , which consisted of entire European and South American teams brought to the US and given local names , and the unsanctioned National Professional Soccer League .