 Nyorai kuenderera mberi kweiyi ndima - Muna 2015, Ertz akarasikirwa nehafu yeiyo NWSL mwaka nekuda kwekuzvipira neUnited States yevakadzi yenyika timu paFIFA Womens World CupmuCanada. Akadzokera kuRed Stars musi waChikunguru 22 panguva yemutambo wakanangana neBoston Breakers, iyo yakapera mukukunda 21 kweRed Stars. Akaita 11 kuoneka kweRed Stars mumwaka wa2015, achitamba maminetsi mazana mapfumbamwe nemakumi mapfumbamwe. The Red Stars vakapedza wechipiri mumwaka wenguva dzose ane 839 chinyorwa uye mberi kuti playoffs. The Red Stars yakatarisana neFC Kansas City mumasemi-fainari emutambo wekupedzisira musi waGunyana 13. Ertz akatanga mumutambo, uyo wakapera mukukundwa kwe0 3 kweRed Stars uye vakabviswa mumutambo. Kutevera mwaka wa2015, Ertz akatumidzwa kuNWSL Best XI. 