Imprisoned fashionable team (6)
I believe the answer is:
inside
'imprisoned' is the definition.
(I've seen this in another clue)
'fashionable team' is the wordplay.
'fashionable' becomes 'in' (in can mean fashionable or trendy).
'team' becomes 'side' (both can mean a sports team).
'in'+'side'='INSIDE'
(Other definitions for inside that I've seen before include "being held" , "Within - interior" , "Inner surface" , "serving porridge" , "banged up" .)