Shock the French after kick-off? (7)
I believe the answer is:
startle
'shock' is the definition.
(I know that startle is a type of shock)
'the french after kick-off?' is the wordplay.
'the french' becomes 'le' ('the' in French).
'after' is a charade indicator (letters next to each other).
'kick off?' becomes 'start' (start of a football match).
'le' after 'start' is 'STARTLE'.
(Other definitions for startle that I've seen before include "Rattles (anag.)" , "Cause shock to" , "Make jump" , "Cause to feel sudden alarm" , "Surprise greatly, alarm" .)