Ground suitable for rugby football? (4)

I believe the answer is:

oval

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'ground' is the definition.
(cricket ground)

I don't understand how the rest of the clue works.

(Other definitions for oval that I've seen before include "sports ground" , "It's egg-shaped for cricketers" , "London cricket ground" , "Shape of 25" , "form of an egg" .)

I've seen this clue in the Evening Standard.

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