 He appeared more sporadically in 1981–82, making 17 appearances and scoring 1 goal, not playing more than seven league matches in succession.Mills left Forest shortly before the end of 1981–82 to join the Seattle Sounders of the North American Soccer League in March 1982.He made 31 appearances, scored 5 goals and recorded 7 assists in the 1982 North American Soccer League season as Seattle finished first in the Western Division.