Diagnose the problem and criticise (4,5)

I believe the answer is:

find fault

'criticise' is the definition.
(I know that find fault is a more specific form of the action criticise)

'diagnose the problem' is the wordplay.
'diagnose' becomes 'find' (as in finding or diagnosing an issue).
'the problem' becomes 'fault' (fault can mean a problem or error).
'find'+'fault'='FIND-FAULT'

'and' acts as a link.

(Another definition for find fault that I've seen is " Carp".)

I've seen this clue in The Guardian.

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