Capacious playing area, topping for some Aussies (5,5)

I believe the answer is:

baggy green

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

'capacious playing area' is the wordplay.
'capacious playing' becomes 'baggy' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'area' becomes 'green' (green is a kind of area).
'baggy'+'green'='BAGGY GREEN'

Can you help me to learn more?

I've seen this clue in The Guardian.

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