Ordered to put apron in. Not feeling the best (3,2,2,3)

I believe the answer is:

not up to par

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'not feeling the best' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'ordered to put apron' is the wordplay.
'ordered' is an anagram indicator.
'to'+'put'+'apron'='toputapron'
'toputapron' is an anagram of 'NOT UP TO PAR'.

'in' is the link.

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I've seen this clue in the Sydney Morning Herald.

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