Kick-off gets mother back in a frenzy (4)
I believe the answer is:
amok
'in a frenzy' is the definition.
(I've seen this before)
'kick-off gets mother back' is the wordplay.
'kick-off' becomes 'ko'.
'gets' says to put letters next to each other.
'mother' becomes 'ma' (ma is a kind of mother).
'back' says the letters should be written in reverse.
'ko'+'ma'='koma'
'koma' in reverse letter order is 'AMOK'.
(Other definitions for amok that I've seen before include "'Wildly, without self-control (4)'" , "Run thus to be wild and uncontrolled" , "Wild and uncontrollable" , "A state of murderous frenzy" , "(Run) in murderous frenzy" .)