The Champions League is, as its name suggests, a league for champions, the greatest teams in Europe. Sevilla had a pretty bad season, but winning the Europa League earned them a spot in the champions league next season, and with this, I believe they will also prepare ahead, am sure they will want to improve and add more players to their squad. Any team playing in the champions league will make huge preparations towards it. Due to the multiple competitions they will participate in and the fact that it will be a hectic season for them, they will require a more diverse team to cover for fatigue and injuries.
The only means Sevilla will make an impact in the UEFA Champions League is to get new players that will complement the old players. The owner of the club Sevillistas de Nervion S.A should ensure they make funds available to Jose Luis Mendilibar to buy more players. The champions league will be more demanding than the Europe League. The club had a bad La Liga experience last season finishing 12th. For them to be more active both in the Spanish league and the champion league they need more players. Coach Mendilibar would have to be more technical next season because he will have to compete with other top-class coaches. The club was just fortunate to win the game against Roma and they need to use this opportunity to make an impact.