Chelsea, one of the most successful football clubs in England, is currently facing challenges on and off the pitch. The team's defensive performance has been criticized as they struggle to defend against opposition attacks.

The Blues have struggled to keep clean sheets this season, conceding 15 goals so far. This poor defense has put Chelsea at risk of losing their Premier League title to Manchester City, who currently lead the table by three points.

Defenders like Antonio Rudiger, Cesar Azpilicueta, and David Luiz have been performing poorly, failing to provide adequate protection for the backline. Rudiger has been particularly disappointing, missing crucial tackles and showing little aggression on the ball. Azpilicueta, meanwhile, has struggled to stay fit throughout the campaign, limiting his availability for key matches.

Furthermore, Chelsea's midfield duo of Jorginho and Ruben Loftus-Cheek have also been inconsistent. Their lack of creativity and inability to provide support for the defense has left them open to counter-attacks from opposing teams.

In addition to their defensive issues, Chelsea have also struggled with injuries, which has further impacted their performances. The likes of Mateo Kovacic, N'Golo Kante, and Christian Pulisic have all been sidelined due to various injuries, leaving boss Thomas Tuchel without several key players.

To improve their defensive performance, Chelsea must focus on addressing their weaknesses and strengthening their defense. This will require investing in new defenders, such as Kalidou Koulibaly or Andreas Christensen, who can provide more stability and leadership on the pitch.

Additionally, the club should look to strengthen their midfield, bringing in a creative midfielder who can provide the necessary support for the defense. This could be achieved through loan deals or transfer windows.

Finally, the team needs to work on their fitness levels, ensuring that every player is ready to play at any time. This will not only help the team perform better defensively but also increase their overall level of play.

Overall, Chelsea's defensive struggles are a major concern for the club. However, by addressing these issues, the team can regain their form and compete for the league title once again.