Swore what Emirates official did's not right (5)

I believe the answer is:

effed

'swore' is the definition.

'what emirates official did's not right' is the wordplay.
'what emirates official did' becomes 'reffed' (Emirates is a football stadium).
'not' indicates named letters should be taken away.
'right' becomes 'r' (common abbreviation).
'reffed' with 'r' taken out is 'EFFED'.

I've seen this clue in The Guardian.

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