Without fail, staggering blearily (8)

I believe the answer is:

reliably

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'without fail' is the definition.
Both the answer and definition are adverbs. Perhaps you can see an association between them that I don't see?

'staggering blearily' is the wordplay.
'staggering' is an anagram indicator (letters stagger around).
'blearily' with letters rearranged gives 'RELIABLY'.

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I've seen this clue in The Everyman puzzle in The Observer.

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