Fantastic Leicester won – a song for the spectators? (5,8)

I believe the answer is:

sweet caroline

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'song for the spectators?' is the definition.
I can't judge whether this definition defines the answer.

'fantastic leicester won a' is the wordplay.
'fantastic' is an anagram indicator (a fantastic or improbable ordering of the letters).
'leicester'+'won'+'a'='leicesterwona'
'leicesterwona' with letters rearranged gives 'SWEET CAROLINE'.

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I've seen this clue in The Guardian.

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