Manchester United still have a big problem to tackle especially, corner kicks. Last season, United conceded several goals from corner kicks and this season, it looks like the same thing might happen. Amorim should work on the players, make them take full responsibility of defending the post and macking their opponents whenever, there is a corner kick.
They conceive so much from not just coner kicks but from set pieces, they need work on their defence tactics against set pieces, they should also train the keeper more to be very watchful during set pieces so they have a chance to reduce the number of goals they concede from set pieces this season as that will also help them with keeping some good records for the team and even for the purpose of their chase for a better position this season.