Faultless boxing succeeded, getting boxer's prize (5)
I believe the answer is:
purse
'boxer's prize' is the definition.
(I've seen this in another clue)
'faultless boxing succeeded' is the wordplay.
'faultless' becomes 'pure' (I've seen this in another clue).
'boxing' is an insertion indicator ('box' can mean contain, as in to put in a box).
'succeeded' becomes 's' (genealogical abbreviation).
'pure' placed around 's' is 'PURSE'.
'getting' is the link.
(Other definitions for purse that I've seen before include "Contract, crease" , "Money-pouch" , "Prize funds" , "Money container" , "sometimes with strings attached?" .)