Demonstrated cunning in club? (7)
I believe the answer is:
marched
'demonstrated' is the definition.
('march' can be a synonym of 'demonstrate')
'cunning in club?' is the wordplay.
'cunning' becomes 'arch' (arch can mean cunning or tricksy).
'in' is an insertion indicator.
'club?' becomes 'med' (I can't justify this - if you can you should believe this answer much more).
'arch' going inside 'med' is 'MARCHED'.
Can you help me to learn more?
(Other definitions for marched that I've seen before include "Walked in step" , "took part in moving protest" , "Walked with measured strides" , "Moved with measured strides" .)