A chance one is fortunate to get (5,5)

I believe the answer is:

lucky break

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'a chance one' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'fortunate to get' is the wordplay.
'fortunate' becomes 'lucky' (synonyms).
'to get' becomes 'break' (I am not sure about this - if you are sure you should believe this answer much more).
'lucky'+'break'='LUCKY BREAK'

'is' is the link.

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I've seen this clue in The Globe and Mail.

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