Everyman's run into lav: behold, Everyman's in a muddle (9)
I believe the answer is:
imbroglio
'a muddle' is the definition.
'everyman's run into lav behold everyman's' is the wordplay.
'everyman's' becomes 'I'm' (where the setter is Everyman).
'run' becomes 'r' (cricket abbreviation).
'into' means one lot of letters goes inside another.
'lav' becomes 'bog'.
'behold everyman' becomes 'lio' (I can't explain this - if you can you should give a lot more credence to this answer).
'r' put into 'bog' is 'brog'.
'im'+'brog'+'lio'='IMBROGLIO'
'in' is the link.
Can you help me to learn more?
(Other definitions for imbroglio that I've seen before include "Confused situation results" , "Dilemma" , "massive jam" , "Oilrig mob (anag.)" , "Complicated situation" .)