#1 Lack of a clinical striker
Diego Costa is gone, and even if the Blues' administration refuses to admit it, he is being missed. Chelsea now miss that well-needed aggression, and summer signing Alvaro Morata has been woefully inconsistent, and hasn't yet set the league on fire.
While his first season so far hasn't been poor by any standards, it just has not been enough for a team that happens to be defending the league title.
The Blues now have another home game as they next face Norwich in the replay of their 3rd round match of the FA Cup, at Stamford Bridge. It will be interesting to see the changes that Conte rings in for the upcoming match as he's bound to be dissatisfied with last night's performance.
Michy Batshuayi will see this as a big opportunity, and he could be expected to start and try and mount a challenge for a regular spot in Chelsea's starting 11.