I think if they wanted to fire Potter they had to fire him weeks ago because even if they hire another coach to start working on Chslea he will need some time to work with the team and change the mistakes Potter did in this team which will need some time while only two weeks left for Chelsea to face Real Madrid in a tough game which can be even harder if they have a new coach who is not familiar with the team.
They should do that weeks ago but it happened and they can not revert time to change anything. So far they have yet appointed a new coach and this action puts their competitiveness in quarter final in big questions. They don't have good performance in this season especially recently and it's hard for me to find positive signals from Chelsea before big matches with Real Madrid.
it is likely that Real Madrid will benefit from Chelsea recent instability, even Real Madrid is not an arbitrary team in the ucl because it is so strong in every match. maybe the percentage of real madrid chances in the first leg to win the game will be bigger because their current squad has no injured players and all the core players are in pretty good condition like Benzema who is back sharp on the front lines.
Without latest instability and changes in Chelsea, Real Madrid are already stronger than Chelsea. Latest matches of both clubs in La Liga and Premier League only make me think that Real Madrid have bigger chance to beat Chelsea than a few weeks ago. Real Madrid just got their best attacking power back with Benzema is on fire again. Vinicius Junior is simply unstoppable with his youth strength, speed and dribbling skills. In addition, he and Benzema find each other very well especially Vini with many good passes for Benzema.