Inept, boring team at Euros (7)
I believe the answer is:
amateur
'inept' is the definition.
(I've seen this before)
'boring team at euros' is the wordplay.
'boring' says the answer is hidden in the clue (the solution has bored or cut into the clue).
'AMATEUR' can be found hidden inside 'team at euros'.
(Other definitions for amateur that I've seen before include "lacking professional expertise" , "Layman" , "Non-pro" , "A non-professional sportsman" , "hobbyist" .)