A joke that's been told often? Told ten such, sadly (3,8)

I believe the answer is:

old chestnut

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'a joke that's been told often?' is the definition.
I don't know anything about this answer so I can't tell whether this works.

'told ten such sadly' is the wordplay.
'sadly' is an anagram indicator.
'told'+'ten'+'such'='toldtensuch'
'toldtensuch' with letters rearranged gives 'OLD CHESTNUT'.

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I've seen this clue in The Everyman puzzle in The Observer.

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