Exhausted with no holds barred (5)

I believe the answer is:

allin

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

'exhausted with no' is the wordplay.
'exhausted with' becomes 'alli' (I can't justify this - if you can you should believe this answer much more).
'no' becomes 'n' (common abbreviation).
'alli'+'n'='ALLIN'

Can you help me to learn more?

I've seen this clue in The Irish Independent.

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