Pay back bruiser, with me being beaten up (9)
I believe the answer is:
reimburse
'pay back' is the definition.
(thesaurus)
'bruiser with me being beaten up' is the wordplay.
'with' means one lot of letters go next to another.
'being beaten up' indicates anagramming the letters.
'bruiser'+'me'='bruiserme'
'bruiserme' is an anagram of 'REIMBURSE'.
(Other definitions for reimburse that I've seen before include "Pay back (e.g. expenses)" , "Compensate for money already spent" , "Repay a person who has spent or lost money" , "refund" , "Repay (a sum of money)" .)