Opening games without associate (9)

I believe the answer is:

sallyport

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'opening' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'games without associate' is the wordplay.
'games' becomes 'sport' (sporting games).
'without' indicates putting letters inside ('without' can be similar in meaning to 'outside').
'associate' becomes 'ally' (ally is a kind of associate).
'sport' going around 'ally' is 'SALLYPORT'.

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

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