Swimmer's bloody outdated style (9)

I believe the answer is:

redmullet

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'swimmer's' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'bloody outdated style' is the wordplay.
'bloody' becomes 'red'.
'outdated style' becomes 'mullet' (I've seen this before. I am not sure about the 'outdated' bit.).
'red'+'mullet'='REDMULLET'

Can you help me to learn more?

I've seen this clue in The Guardian.

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