Two visits to the loo, runs very bad (4-4)

I believe the answer is:

piss-poor

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'two visits to the loo runs' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'very bad' is the wordplay.
'very' becomes 'piss' (I can't justify this - if you can you should give a lot more credence to this answer).
'bad' becomes 'poor' (similar in meaning).
'piss'+'poor'='PISS-POOR'

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