Defunct fixtures need replacement (3,4,5)

I believe the answer is:

six feet under

'defunct' is the definition.
(six feet under means dead)

'fixtures need replacement' is the wordplay.
'replacement' is an anagram indicator.
'fixtures'+'need'='fixturesneed'
'fixturesneed' is an anagram of 'SIX FEET UNDER'.

(Another definition for six feet under that I've seen is " Dead and buried".)

I've seen this clue in The Guardian.

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