Refills excellent drink (4,2)

I believe the answer is:

tops up

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'refills' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'excellent drink' is the wordplay.
'excellent' becomes 'top' (top can mean the best).
'drink' becomes 'sup' (to sup is to drink).
'top'+'sup'='TOPS UP'

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I've seen this clue in The Irish Times.

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