The Athletic v United clash was decided by an early red card in the first leg. It could have gone differently, but it was decided after that. Athletic played very well in the return game, but unfortunately their peculiarity is that when there is no practical sense in playing, they fall apart, so the second game also ended in a rout. But still, these results do not reflect the real balance of power in this pair.
The red card decided the winner in the first leg because it really affected the performance of the home team. But Athletic Club failed to take advantage of the second leg when they lost 4-1. Generally, I think that Manchester United was a better team and decided to progress to the finals. The Red Devils might not be in good form in the Premiership but it seems they are destined to be in the Europa League since they have been having good results and enjoying an unbeaten run.