Rubuta ci gaba don wannan sakin layi - A watan Afrilu na 2015, ya sanya hannu kan kwangilar shekara guda don buga wasan Leinster. Ya dawo Leinster ne a wasan da suka buga da Edinburgh Rugby a kakar 2015-16 Pro 12
yana bugun maki 9. A mako mai zuwa, shi ne kyaftin din kuma ya ci maki 13 don taimakawa Leinster ya doke Cardiff Blues. Ya taka leda a duka wasanni biyu. Nacewa ya tsawaita kwantiraginsa kuma an sanya shi a matsayin Kyaftin Leinster na kakar 2015/16. An nada Nacewa kyaftin din kungiyar Pro 12 na kakar wasa yayin da ya jagoranci Leinster zuwa saman teburin Pro 12 da wasan karshe a Murrayfield inda Connacht Rugby ta doke su da 20-10.