Old glen destroyed without support (2,3)

I believe the answer is:

no leg

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

'old glen destroyed without' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'destroyed' is an anagram indicator.
'without' is an insertion indicator.
'glen' with letters rearranged gives 'nleg'.
'o' put into 'nleg' is 'NO LEG'.

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

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