Her coach , Andrey Matrosov , stands on the opposite baseline next to a bucket of yellow balls .
Kseniya Alyeshina , who will soon celebrate her 10th birthday , is one of Russia 's top - ranked players in her age group .
Kseniya Alyeshina 's coach , Andrey Matrosov , stands on the opposite baseline next to a bucket of yellow balls .
Kseniya Alyeshina , who will soon celebrate her 10th birthday , is one of Russia 's top - ranked players in her age group .