#3 Sevilla's comfort; United's grief
On three previous occasions when Sevilla reached the Europa League semi-final (2014, 2015, 2016), they went on to lift the trophy. What is even more interesting is the fact that they have only been defeated in one of their past 20 knockout ties in the Europa League, losing 6-5 on aggregate to Slavia Prague in the last 16 in 2018-19 season.
Meanwhile, Manchester United are yet to win a trophy under Solskjaer. In fact, they last won a cup in the 2016/17 season, lifting the Europa League under Jose Mourinho. They've already lost two semi-finals this season. Many of the current Manchester United players are not well acquainted with big occasions unlike their Sevilla counterparts.
#2 Manchester United starters are fatigued
The likes of Harry Maguire and Bruno Fernandes have started nearly every single game since the restart. And post the Covid break, the games have been coming thick and fast and there really has been hardly any time to recover for the players.
Of course then it doesn't help that Manchester United do not have quality squad depth and there is a gulf in class between their starters and substitutes. For example, you simply cannot expect the same kind of productivity from Jesse Lingard or Andreas Pereira as Bruno Fernandes.
Anthony Martial has looked good and so has Marcus Rashford. But Greenwood might find it difficult to cope as he is still just 18-years-old. The fact that the last game against Copenhagen went into extra time certainly does not help. Sevilla are slightly better rested in that regard.
#1 Sevilla full-backs could disrupt Manchester United's flow
With Luke Shaw unavailable, Ole Gunnar Solskjaer has to rely on Brandon Williams. Though the youngster is pretty impressive himself, both his and Aaron Wan-Bissaka's offensive game leaves a lot to be desired.
Tonight, the Manchester United full-backs are expected to have their hands full in a defensive sense as both Jesus Navas and Sergio Reguilon are both excellent in joining the attack and whipping in dangerous balls into the area.
Manchester United rely on their full-backs holding a high line and interchanging positions with Rashford and Greenwood. However, Sevilla might be a whole different proposition with regard to this aspect. If the United full-backs are constantly kept busy in their own half, then it could severely hamper Manchester United's flow going forward.