Ainsley signed for Football League Third Division side Hartlepool United from Spennymoor in June 1994.
[4] After leaving Hartlepool, Ainsley played for several English non-league sides as well as for clubs in Australia and Singapore.
[5] In 2006, Ainsley was appointed as manager of Northern League Division Two (the tenth tier of English football) side Spennymoor.
[7][8] Ainsley was the longest-serving manager in the top seven divisions of English football when he left Spennymoor in 2020.
[10] Ainsley guided Spennymoor to the National League North (6th tier), the highest division in their history.