Boxer dog I put up for sale (8)

I believe the answer is:

pugilist

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'boxer' is the definition.
(I know that boxer can be written as pugilist)

'dog i put up for sale' is the wordplay.
'dog' becomes 'pug' (pug is a kind of dog).
'put up for sale' becomes 'list' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'pug'+'i'+'list'='PUGILIST'

Can you help me to learn more?

(Other definitions for pugilist that I've seen before include "A professional boxer" , "Fist fighter" , "Prize fighter" .)

I've seen this clue in The Independent.

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