Defenders greeted, sloping off from the front (9)

I believe the answer is:

backswept

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'sloping off from the front' is the definition.
I can't tell whether this defines the answer.

'defenders greeted' is the wordplay.
'defenders' becomes 'backs' (I've seen this before).
'greeted' becomes 'wept' (I can't justify this - if you can you should give a lot more credence to this answer).
'backs'+'wept'='BACKSWEPT'

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I've seen this clue in The Guardian.

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