Stu Holcomb, athletic director at Northwestern University, was hired to act as the team's general manager.

[2] The USA originally planned to start play in the spring of 1968; however the rival National Professional Soccer League, which secured a TV contract from CBS, announced it was ready to launch in 1967.

Not having secured any player contracts, the league imported teams from Europe, Brazil, Argentina and Uruguay to represent the franchise cities.

[5] [6] The Mustangs finished the 1967 season in third place of the Western Division with a record of 3 wins 7 ties and 2 loses and an average attendance of 4,207.

[8][a] The Mustangs finished the 1968 NASL season in second place of the Lakes Division with a record of 13 wins 9 ties and 10 loses and an average attendance of 2,463.