Cuff at last sadistic hooligan (5)
I believe the answer is:
clout
'cuff' is the definition.
(I've seen this before)
'last sadistic hooligan' is the wordplay.
'last' says to take the final letters.
'hooligan' becomes 'lout' (both can mean an aggressive person).
The last letter of 'sadistic' is 'c'.
'c'+'lout'='CLOUT'
'at' acts as a link.
(Other definitions for clout that I've seen before include "Blow to the head" , "Sock" , "Cuff" , "Cast not one before May is out" , "hit hard" .)