Curse dodgy merchant regularly displaying neglected pet (6,3)

I believe the answer is:

rescue cat

'neglected pet' is the definition.
(cat which has been rescued)

'curse dodgy merchant regularly' is the wordplay.
I cannot really understand how this works, but
an anagram of 'curse' is 'rescu' which is within the answer.
This explanation may well be incorrect...

'displaying' is the link.

I've seen this clue in The Independent.

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