Marathon winner appearing in racecourse (9)

I believe the answer is:

longchamp

'racecourse' is the definition.
(I've seen this before)

'marathon winner' is the wordplay.
'marathon' becomes 'long' (marathon can mean long or lengthy).
'winner' becomes 'champ' (I've seen this before).
'long'+'champ'='LONGCHAMP'

'appearing in' is the link.

(Another definition for longchamp that I've seen is " Racecourse".)

I've seen this clue in The Times.

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