Fighter in conflict right behind city (7)
I believe the answer is:
warrior
'fighter' is the definition.
(I know that fighter can be written as warrior)
'conflict right behind city' is the wordplay.
'conflict' becomes 'war' (war is a kind of conflict).
'right' becomes 'r' (common abbreviation).
'behind' means one lot of letters go next to another.
'city' becomes 'rio' (Rio de Janeiro).
'r' put after 'rio' is 'rior'.
'war'+'rior'='WARRIOR'
'in' acts as a link.
(Other definitions for warrior that I've seen before include "Person engaged in battle" , "Person experienced in battle" , "Combatant" , "Skilled fighting man" , "Fighting soldier" .)