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 Bilbao VS Manchester United match is clearly not balanced and it cannot be denied that Manchester United is far superior in this match. Because in the first leg, when Bilbao's players were still complete (before getting a red card) Manchester United had managed to score 1 goal. This also explains that Manchester United is indeed superior to Bilbao. Then in the second leg, Bilbao did play quite well, especially in its defense. But unfortunately it did not continue to go well, because entering the 70th minute Bilbao's defense worsened again and Manchester United managed to score 4 goals after that. So basically the quality of Bilbao's players is indeed inferior in every aspect to Manchester United's players. Although Bilbao also has quite good players, such as Nico William and Inaki. But still the two players were not able to do much. Moreover, as I recall in the second leg Nico and Inaki did not play. This is also what might be the reason why Bilbao conceded more goals in the second leg. But never mind, the match is over and now we have to focus on the Europa League final which will definitely be much more exciting and tense.