Two football teams without arrogance among stars (13)

I believe the answer is:

intersidereal

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'among stars' is the definition.
I can't judge whether this defines the answer.

'two football teams without arrogance' is the wordplay.
'two football teams' can mean two substitutions for 'football team'.
'football team' becomes 'inter' (short for Inter Milan, Italian football team).
'football team' becomes 'Real' (Real Madrid).
'without' means one lot of letters goes inside another ('without' can be similar in meaning to 'outside').
'arrogance' becomes 'side' (I've seen this before).
'inter'+'real'='interreal'
'interreal' enclosing 'side' is 'INTERSIDEREAL'.

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I've seen this clue in The Guardian.

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