Requisite care expected by old coach (3,9)

I believe the answer is:

due diligence

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'requisite care' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.

'expected by old coach' is the wordplay.
'expected' becomes 'due' (similar in meaning).
'by' means one lot of letters go next to another.
'old coach' becomes 'diligence' (historical type of stagecoach).
'due'+'diligence'='DUE DILIGENCE'

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

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