Head salesman to criticise returns (6)

I believe the answer is:

napper

'head' is the definition.
(informal term for someone's head)

'salesman to criticise returns' is the wordplay.
'salesman' becomes 'rep' (sales rep).
'to criticise' becomes 'pan' (informal term meaning to criticise heavily).
'returns' says the letters should be written backwards.
'rep'+'pan'='reppan'
'reppan' reversed gives 'NAPPER'.

I've seen this clue in The Guardian.

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