Put an end to sock fluff (6,4)

I believe the answer is:

strike down

'put an end to' is the definition.
(to strike down is to kill or put an end to)

'sock fluff' is the wordplay.
'sock' becomes 'strike' (sock can mean to hit or punch).
'fluff' becomes 'down' (I've seen this in another clue).
'strike'+'down'='STRIKE DOWN'

I've seen this clue in The Telegraph.

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