Golf -- brutal boy ruined game (5,8)

I believe the answer is:

rugby football

'game' is the definition.
(rugby football is a kind of game)

'golf brutal boy ruined' is the wordplay.
'ruined' is an anagram indicator.
'golf'+'brutal'+'boy'='golfbrutalboy'
'golfbrutalboy' is an anagram of 'RUGBY FOOTBALL'.

I've seen this clue in The Telegraph.

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