Leverkusen doesn't really have that many resting period, the only thing I worry about that game would be the fatigue. They have a game at 18th, and the finals at 22nd but also their dfk pokal game will be at 25th as well. So, they are going to play 3 games in 1 week during that period, after that all the players will be at vacation basically so it is fine, and they did played three games a week before, but this is end of the season and it will definitely be something that will tire all of them out without a doubt.
This is why I believe that it is going to be a tough situation without a doubt. I personally believe that they should probably consider resting some players on 18th during league game, may risk their unbeaten status, but would get them the title against Atalanta.
Those players are strong, agile and very smart. They will not have any problem of fatigue because I know that they should be used to this kind of unending football matches, and that is what will make them stronger than any club that they will be playing. Strong teams and players don't get weighed down with fatigue.
Who knows if that is how they plan to prepare for the finals so that they will be fit at all time. Xabi Alonso knows what he is doing and I believe his coaching skills and decisions.
It makes sense, the fatigue factor will certainly be the biggest challenge for Leverkusen, where Atalanta is actually also in the same situation. the two coaches must be very wise in determining the starting XI in domestic matches before facing each other in the Europa League Final. Xabi has managed to overcome various kinds of doubts and also various kinds of pressure, the player fatigue factor seems to be only a small problem for them.
Looking at the 50 unbeaten matches, it shows that Xabi is quite a genius in determining the starting XI. In many matches, the player rotations he made went according to plan, so that the player fatigue factor could always be handled well. In addition, this method has saved players from injury, one of the biggest indicators and luckiest for Leverkusen this season, they have avoided an injury storm.
Meanwhile, before facing Leverkusen in the Europa League final, Atalanta had to face Juventus in the Coppa Italia final first, after two days Atalanta had to play another Serie A match against Lecce. Meanwhile, Leverkusen only has one match, namely against Augsburg in the last week of the Bundesliga. If you look at the match schedule, Leverkusen has more time to prepare.