Kit appears in large arena (4)
I believe the answer is:
gear
'kit' is the definition.
(I've seen this before)
'in large arena' is the wordplay.
'in' indicates the answer is hidden within the clue.
'GEAR' is hidden within 'large arena'.
'appears' is the link.
(Other definitions for gear that I've seen before include "Clothes -- paraphernalia" , "Outfit - equipment - changed on inclination?" , "Clothes (first or second, perhaps?)" , "working order" , "Clothing - tackle" .)