Coach then court conductor (6)

I believe the answer is:

busbar

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'conductor' is the definition.
(I know that busbar is a type of conductor)

'coach then court' is the wordplay.
'coach' becomes 'bus' (synonyms).
'then court' becomes 'bar' (I can't explain this - if you can you should believe this answer much more).
'bus'+'bar'='BUSBAR'

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I've seen this clue in The Times.

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