Chelsea's defensive problems have been well-documented over the past few seasons. The Blues have struggled to keep their opponents at bay, conceding goals in matches that have become increasingly common.

One of Chelsea's biggest problems has been their lack of depth in the defense. The club has relied heavily on players like Andreas Christensen and Cesar Azpilicueta, who have both played a significant role in the team's success. However, these two players are not invincible, and they can be vulnerable when they are injured or out of form.

Another issue with Chelsea's defense is their inability to deal with set-pieces. The Blues have conceded many goals from set pieces this season, which has contributed to their poor performance in the Premier League.

In addition to these issues, Chelsea also need to address their overall organization in the backline. The team's defense has often looked disorganized and unsure of themselves, which has led to them being caught off guard by opposing teams' attacks.

To address these problems, Chelsea will need to make some serious changes to their defense. They may need to sign new defenders to add depth to their squad, or they could look to improve the current players through training and tactics.

Overall, Chelsea's defensive problems are a major concern for the team, and it will take some time and effort to solve them. However, if the club can address these issues, there is no doubt that they will be able to compete at the highest level once again.