It comes top in rigged contests (12)

I believe the answer is:

competitions

'contests' is the definition.
('competition' can be a synonym of 'contest')

'it comes top in rigged' is the wordplay.
'rigged' indicates anagramming the letters.
'it'+'comes'+'top'+'in'='itcomestopin'
'itcomestopin' is an anagram of 'COMPETITIONS'.

I've seen this clue in The Telegraph.

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