Bend the rules (previously following) (4)
I believe the answer is:
flex
'bend' is the definition.
(I know that bend can be written as flex)
'rules previously following' is the wordplay.
'rules' becomes 'lex' (I am not sure about this - if you are sure you should believe this answer much more).
'previously' is a charade indicator (letters next to each other).
'following' becomes 'f' (used when citing page numbers etc).
'lex' put after 'f' is 'FLEX'.
'the' is the link.
Can you help me to learn more?
(Other definitions for flex that I've seen before include "Bendable cord" , "Electrical power cord" , "Bend (muscle?)" , "Bend - electrical cable" , "Contract (a muscle)" .)