Took in EU busting tennis organisation (5)

I believe the answer is:

ateup

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'busting tennis organisation' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'took in eu' is the wordplay.
'took in' becomes 'ate' (take in can mean to eat).
'eu' becomes 'up' (I can't explain this - if you can you should believe this answer much more).
'ate'+'up'='ATEUP'

Can you help me to learn more?

I've seen this clue in The Irish Times.

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