Philistine needs hours in gaol to fight a criminal (7,2,4)

I believe the answer is:

goliath of gath

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

'hours in gaol to fight a criminal' is the wordplay.
'hours' becomes 'h'.
'in' indicates putting letters inside.
'criminal' is an anagram indicator.
'gaol'+'to'+'fight'+'a'='gaoltofighta'
'gaoltofighta' with letters rearranged gives 'goliatofgath'.
'h' inserted within 'goliatofgath' is 'GOLIATH OF GATH'.

'needs' acts as a link.

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I've seen this clue in The Guardian.

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