Novak Djokovic or Nikola Jokic, by birth (4)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
serb
(Other definitions for serb that I've seen before include "Eg, native of Belgrade" , "Someone from Belgrade?" , "From Belgrade, perhaps" , "Native of the Balkans" , "Balkan native" .)