Joins Portuguese participants for fun (2,5)

I believe the answer is:

in sport

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

'joins portuguese participants' is the wordplay.
'IN SPORT' is hidden within the letters.
However, I am uncertain how this is indicated.

'for' is the link.

Can you help me to learn more?

I've seen this clue in The Irish Times.

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