No team at this stage is considered to be a weak team maybe we could consider some as underdogs. If we look at Manchester United previous matches against Spanish teams they always have it hard but the both legs against Barcelona was different. We could mainly say it was because of Barcas lack of consistency in European competitions but also we have to give credit to Ten Hag on the kind of project he is building currently at Manchester United. I will predict a Manchester United progression to the Last 8 because Real Betis will be without their key player; Naby Fekir, and it will create a huge imbalance in the team
Real Betis joined a competition with Sociedad and Atletico Madrid to be in the ECL next season so they can't let La Liga and focus on the match against Man United. On Sunday, they are going to face Real Madrid at home, so this match could consume a lot of their energy before the match against Man United. In the meantime, Man United has the same situation in the EPL, as they are going to face Liverpool. Therefore, I think substitutions and match management will play great role in deciding the qualified team, which I think will be Man United.