On 9 December 2014, Maitland-Niles made his professional debut at the age of 17 years and 102 days in a UEFA Champions League match against Galatasaray.
Den 9 Dezember 2014 huet Maitland-Niles säin professionellt Debut am Alter vu 17 Joer a 102 Deeg an engem UEFA Champions League Match géint Galatasaray gemaach.