Slot addressed his injury problems in a pre-match press conference, earlier this week.
He said: "Even if you would reconsider and you come to a different decision, then the question is are we able to change it? Can we make this squad bigger with the money available and the things we can do?
"We are maybe one or two players short compared to last season in terms of numbers, and if you add then three long-term injuries to that, then all of a sudden it is quite a lot.
"This is not going to be a popular opinion what I am going to tell you now. But maybe the reason we won the league last season is we had to play Paris Saint-Germain in the last 16, because as you know they beat us and we had every time a week to prepare for our next game.
"We are aware, every manager is aware, the bigger squad you have, the better equipped you are for so many games. But I am also aware of the fact that even today I had to disappoint one or two players that would prefer to play.
"Now if you have 10 or 15 who want that, that is also not a good thing to have. It is not an easy balance to find, but obvious because of the three long-term injuries, now it is a imbalance, that is obvious."