A game between two sides back in the country (5)
I believe the answer is:
rural
'in the country' is the definition.
(I've seen this before)
'a game between two sides back' is the wordplay.
'game' becomes 'ru' (rugby union).
'between' means one lot of letters goes inside another.
'two sides' becomes 'lr' (**).
'back' is a reversal indicator.
'a'+'ru'='aru'
'aru' put into 'lr' is 'larur'.
'larur' written backwards gives 'RURAL'.
(Other definitions for rural that I've seen before include "Bucolic; pastoral" , "Agrestic" , "Countrylike" , "Characteristic of country life" , "Rustic" .)