The saint's awful blemish (5)

I believe the answer is:

stain

'blemish' is the definition.
(stain is a kind of blemish)

'the saint's awful' is the wordplay.
'awful' is an anagram indicator.
'saint' with letters rearranged gives 'STAIN'.

(Other definitions for stain that I've seen before include "Smear" , "Blotch on satin" , "Mark with colour, dirt" , "Discoloration" , "Blot" .)

I've seen this clue in The Irish Independent.

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