Fight a persistent battle, getting furious (8,8)

I believe the answer is:

spitting feathers

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'fight a persistent battle getting furious' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'fight a persistent battle' is the wordplay.
'battle' is an anagram indicator (the letters disrupted as if in battle).
'fight'+'a'+'persistent'='fightapersistent'
'fightapersistent' is an anagram of 'SPITTING FEATHERS'.

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I've seen this clue in The Guardian.

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