Slightly deviant aga's cunningly constrained (2,1,12)

I believe the answer is:

at a disadvantage

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'slightly deviant aga's cunningly constrained' is the definition.
I can't judge whether this defines the answer.

'slightly deviant aga's cunningly' is the wordplay.
'slightly' becomes 'atad' ('a tad' can mean 'slightly' or 'a bit').
'cunningly' is an anagram indicator (a cunning or tricky form of the letters).
'deviant'+'agas'='deviantagas'
'deviantagas' anagrammed gives 'isadvantage'.
'atad'+'isadvantage'='AT A DISADVANTAGE'

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I've seen this clue in The Daily Express.

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