Disorganised mafiosi centrally involved in violent mob clash (9)
I believe the answer is:
shambolic
'disorganised' is the definition.
(I've seen this before)
'mafiosi centrally involved in violent mob clash' is the wordplay.
'centrally' says to take the centre.
'involved in' means one lot of letters goes inside another.
'violent' indicates an anagram.
The middle of 'mafiosi' is 'i'.
'mob'+'clash'='mobclash'
'mobclash' with letters rearranged gives 'shambolc'.
'i' put into 'shambolc' is 'SHAMBOLIC'.
(Other definitions for shambolic that I've seen before include "Chaotic, mismanaged" , "Chaotic and inefficient" , "In a total mess" , "Disorderly" , "all over the place?" .)