A lot of depressed jockeys, those who are racing (8)

I believe the answer is:

speeders

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'those who are racing' is the definition.
The definition suggests an adverb but the answer is not.

'a lot of depressed jockeys' is the wordplay.
'a lot of' means to remove the first letter.
'jockeys' is an anagram indicator.
'depressed' with its first letter removed is 'epressed'.
'epressed' anagrammed gives 'SPEEDERS'.

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I've seen this clue in The Independent.

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