This is a sign of frustration from Amorim. Didn't he say he wouldn't change his formation, loudly declaring it all depended on him? Now, a change in formation signals Amorim surrender and a gamble. Like it or not, Sunderland comes into the Premier League this season with incredible motivation, so I wouldn't be surprised if Manchester United lose. Sunderland six matches have 3W, 2D, and 1L, making them quite optimistic for a visit to Old Trafford.
Sunderland are off to a great start this season. Yes, the match is definitely a threat for United, because Sunderland's recent performance shows how good they are at winning. It certainly won't be good for Amorim if they lose or draw against Sunderland, because they will be playing at home. I don't know why United management is not doing anything positive towards changing the coach yet, because I can see how Ruben Amorim is being given chances again and again and he is failing again. The start of this season has not been good for Manchester United either, their defeat percentage in 6 matches is 50%. This certainly does not indicate a good position for a team.