An exclamation of quality heartache (4,5)

I believe the answer is:

good grief

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'an exclamation' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'quality heartache' is the wordplay.
'quality' becomes 'good' (good is a kind of quality).
'heartache' becomes 'grief' (synonyms).
'good'+'grief'='GOOD GRIEF'

'of' acts as a link.

Can you help me to learn more?

(Other definitions for good grief that I've seen before include "Exasperated utterance" , "Oath given surprisingly" , "I'm dismayed!" , "Exclamation of surprise or dismay" .)

I've seen this clue in the Sydney Morning Herald.

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