The hosts needed a late goal from Vinicius Jr to earn a 1-1 draw with La Real.
Schuster said: “I think that Real Madrid did not deserve to lose. La Real was better in the second half, but I don't think either of them deserved to win.
"This squad is very limited, it is very difficult for Real Madrid to fight with teams with better structured squads.
"Even if (Karim) Benzemá or (Sergio) Ramos are there, there is a lot of gaps to take advantage of."