Remain firmly resolved to execute ruffian (4,5)

I believe the answer is:

hang tough

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'remain firmly resolved' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'execute ruffian' is the wordplay.
'execute' becomes 'hang' (hanging is a kind of executing).
'ruffian' becomes 'tough' (I can't justify this - if you can you should believe this answer much more).
'hang'+'tough'='HANG TOUGH'

'to' acts as a link.

Can you help me to learn more?

I've seen this clue in The Guardian.

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