Haggard book, perhaps, is something from the sewer? (5,4)

I believe the answer is:

drawn work

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'something from the sewer?' is the definition.
I know nothing about this answer so I cannot tell whether this works.

'haggard book perhaps' is the wordplay.
'haggard' becomes 'drawn' (synonyms).
'book perhaps' becomes 'work' (book is a kind of work).
'drawn'+'work'='DRAWN-WORK'

'is' is the link.

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I've seen this clue in The Independent.

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