Plan huge upset after kick-off, moving right up (9)
I believe the answer is:
stratagem
'plan' is the definition.
(stratagem is a kind of plan)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for stratagem that I've seen before include "Start game with cunning plan" , "Artifice" , "Cunning manoeuvre" , "A cunning plan or piece of trickery" , "Tag master with cunning plan" .)