It's played with a round ball (6)

I believe the answer is:

soccer

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'ball' is the definition.
(soccer ball is a kind of ball)

I cannot understand how the remainder of the clue works.

(Other definitions for soccer that I've seen before include "Ball game" , "popular game" , "Football for Americans?" , "... players playing this (colloquially)" , "American football?" .)

I've seen this clue in the Evening Standard.

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