Pressure on football club to get some balls (3,2)

I believe the answer is:

man up

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'get some balls' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'pressure on football club' is the wordplay.
'pressure' becomes 'p' (abbreviation).
'on' means one lot of letters go next to another.
'football club' becomes 'manu' (I can't explain this - if you can you should believe this answer much more).
'p' put after 'manu' is 'MAN UP'.

'to' acts as a link.

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I've seen this clue in The Independent.

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