In my view, Real Madrid basically has a lot of potential young players and as such, Real Madrid should be fine even if some of its key players are injured. Because after all, the purpose of Real Madrid previously brought in many young players was also to make regeneration work well. Thus, currently many of Real Madrid's key players are injured and that should allow Ancelotti to give confidence to the young players in the current Real Madrid squad. If Ancelotti is really able to maximize the potential of the young players available, then surely Real Madrid will still be able to get good results in situations like this.
Real Madrid even have a very brilliant reserve team and why they are yet to effectively put that to use is another things really don't understand and do bother about sometimes, I think it will even be better if they can rest some of this bigger players awhile like they did last season and allow the reserves to play few games as the key players are stressed already, they have the stress from their club side and Still gets almost same from their country sides too when the needs arises so I believe they will get fatigue and injury prone so it will be ideal they are rested at some instance.
I think the same way you do. It is risky for players to play all the time. Especially if your star players play every game, the risk of injury is higher. Considering both the players' fatigue and the possibility of the opponent injuring them, Real Madrid needs to adjust the squad rotation well. Carlo Ancelotti, who gave more chances to the young players last year, is giving less chances this year. I think this is also something he thinks is wrong. He should definitely rest his players in the squad.