Faulty line inscribed in medal I cast (9)

I believe the answer is:

blemished

'faulty' is the definition.
(thesaurus)

'line inscribed in medal i cast' is the wordplay.
'line' becomes 'l'.
'inscribed in' indicates putting letters inside.
'medal' becomes 'bem' (British Empire Medal).
'cast' becomes 'shed' (synonyms).
'l' put within 'bem' is 'blem'.
'blem'+'i'+'shed'='BLEMISHED'

I've seen this clue in The Times.

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