Professional team employs outside agencies (7)

I believe the answer is:

proxies

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'agencies' is the definition.
Although both the answer and definition are plural nouns, I can't see how one could define the other.

'professional team employs outside' is the wordplay.
'professional' becomes 'pro' (synonyms).
'team' becomes 'xi' (eleven, a football team).
'outside' says to hollow out the word (remove centre letters).
'employs' with its middle removed is 'es'.
'pro'+'xi'+'es'='PROXIES'

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

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