Turn back inside to avoid contact with ruler (6)
I believe the answer is:
shogun
'ruler' is the definition.
(shogun is a kind of ruler)
'turn back inside to avoid contact' is the wordplay.
'turn' becomes 'go' (a person's move in a board game).
'back' says the letters should be written in reverse.
'inside' means one lot of letters goes inside another.
'to avoid contact' becomes 'shun' (I've seen this before).
'go' written backwards gives 'og'.
'og' inserted into 'shun' is 'SHOGUN'.
'with' acts as a link.
(Other definitions for shogun that I've seen before include "Dominant Japanese" , "military commander" , "Foreign C-in-C" , "Japanese military dictator" , "Feudal Japanese leader" .)