City score, retaining ball (4)
I believe the answer is:
troy
'city' is the definition.
(Troy is an example)
'score retaining ball' is the wordplay.
'score' becomes 'try' (**).
'retaining' indicates putting letters inside.
'ball' becomes 'o'.
'try' placed around 'o' is 'TROY'.
(Other definitions for troy that I've seen before include "City destroyed" , "The war for it, Homer" , "City besieged by the Greeks - system of weights for gems" , "City impacted by long-term investment" , "City besieged by the Greeks - system of gem weight measurement" .)