Tennis star Becker (5)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
boris
(Other definitions for boris that I've seen before include "- Johnson, Mayor of London" , "Pasternak, perhaps" , "Russian name" , "- Godunov, Mussorgsky opera" , "- Pasternak, Russian author (Doctor Zhivago)" .)