Nottim Forest vs Manchester United would be a tough one, I think United may find a way to get a draw hopefully. All these does not mean I disregard one of the best team of EPL this season along having the best defence.
A new challenge for Man United because this season Nothingham Forest has performed well. Much better than Man United. I think Man United will struggle. A provisional 3rd rank describes Nothingham in good condition. Playing at home is an added strength so wanting a draw for Man United is realistic. But this international break there may be some fatigue and injury factors in players. But I still believe that Nothingham is the favorite to win. Statistically, Nothingham's players seem to have a better mentality.
Nottingham Forest playing at home will certainly be favored to win the match, especially since Nottingham Forest's performance is quite good now and they have high motivation to be able to maintain their position and to be able to finish in the top 4 of the final Premier League standings later.
While Man United this season as a whole does not have a good performance, even in terms of consistency they are still very doubtful so I don't think they will be able to beat Nottingham Forest in the match this weekend.