Inappropriate team from Manchester holding us back (8)
I believe the answer is:
unsuited
'inappropriate' is the definition.
(thesaurus)
'team from manchester holding us back' is the wordplay.
'team from manchester' becomes 'United' (Manchester United football club).
'holding' means one lot of letters goes inside another.
'back' shows that the letters should be reversed in order.
'us' reversed gives 'su'.
'united' enclosing 'su' is 'UNSUITED'.
(Other definitions for unsuited that I've seen before include "United us, being not fit for" , "Mismatched" , "United us, not being harmonious" , "incompatible" .)