Crossword Genius

Croupier’s prompt to cause one negative defeat (2,2,3)

Ross

I believe the answer is:

in or out

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'croupier's prompt to' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'one negative defeat' is the wordplay.
'one' becomes 'i' (Roman numeral).
'negative' becomes 'no' (no is a kind of negative).
'defeat' becomes 'rout' (rout is a kind of defeat).
'i'+'no'+'rout'='IN OR OUT'

'cause' acts as a link.

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I've seen this clue in the Sydney Morning Herald.
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