Blue team reveals limitation (8)
I believe the answer is:
downside
'limitation' is the definition.
(a downside is a limitation or bad feature)
'blue team' is the wordplay.
'blue' becomes 'down' (both can mean sad).
'team' becomes 'side' (both can mean a sports team).
'down'+'side'='DOWNSIDE'
'reveals' is the link.
(Other definitions for downside that I've seen before include "RC school; bad aspect" , "public school" , "Somerset RC abbey/college" , "disadvantage" , "Discouraging aspect" .)