Is being forced to admit wrong replacement of huge mineable pit (6,6,3)

I believe the answer is:

eating humble pie

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'is being forced to admit wrong replacement' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'of huge mineable pit' is the wordplay.
'of' is an anagram indicator (the answer comes from or 'of' the letters).
'huge'+'mineable'+'pit'='hugemineablepit'
'hugemineablepit' with letters rearranged gives 'EATING HUMBLE PIE'.

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

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