Four antecedents went crazy in uphill struggle (4,2,9)

I believe the answer is:

test of endurance

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'crazy in uphill struggle' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'four antecedents went' is the wordplay.
'went' indicates anagramming the letters ('go' can mean move).
'four'+'antecedents'='fourantecedents'
'fourantecedents' anagrammed gives 'TEST OF ENDURANCE'.

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

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