Urgent lack of uncreased shirts? (8,4)

I believe the answer is:

pressing need

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'urgent lack of uncreased shirts?' is the definition.
I can't tell whether this defines the answer.

'urgent lack' is the wordplay.
'urgent' becomes 'pressing' (synonyms).
'lack' becomes 'need' (I've seen this before).
'pressing'+'need'='PRESSING NEED'

Can you help me to learn more?

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

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