Chelsea net, ruining this? (5,5)

I believe the answer is:

clean sheet

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'this?' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'chelsea net ruining' is the wordplay.
'ruining' indicates anagramming the letters.
'chelsea'+'net'='chelseanet'
'chelseanet' with letters rearranged gives 'CLEAN SHEET'.

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I've seen this clue in The Independent.

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