A team on edge? (4)
I believe the answer is:
side
This clue is a double definition.
'a team' is the first definition.
(I've seen this before)
'edge?' is the second definition.
(edge is a kind of side)
'on' is the link.
(Other definitions for side that I've seen before include "superciliousness" , "Dies (anag)" , "Face - team" , "Dies for own team" , "by no means a front" .)