Country way, one guarded by police once (6)

I believe the answer is:

rustic

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'country' is the definition.
(I've seen this in another clue)

'way one guarded by police once' is the wordplay.
'way' becomes 'st' (abbreviation for street).
'one' becomes 'i' (Roman numeral).
'guarded by' is an insertion indicator.
'police once' becomes 'ruc' (I am not sure about the 'once' bit.).
'st'+'i'='sti'
'sti' put into 'ruc' is 'RUSTIC'.

Can you help me to learn more?

(Other definitions for rustic that I've seen before include "Charmingly simple" , "country cousin" , "Countryfied" , "clodhopper" , "Rural, country" .)

I've seen this clue in The Times.

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