But the Spain midfielder has revealed how manager Jose Mourinho demanded more from the squad the moment pre-season began.
He added: “The manager made it very clear the first day we met that we all have to be better than last season. It’s a big challenge for us.
“We are very young, that’s why I’m sure we are capable of progressing into a better team. Hopefully, we can start doing that from tomorrow.”
The strength of Chelsea’s strike-force has come under scrutiny due to Costa’s recurring hamstring injury.
Mourinho does not know if Costa will be fit to start tomorrow and his back-up options are Radamel Falcao, who joined on loan from Monaco, and Loic Remy.
Falcao scored just four times for Manchester United last term while Remy has fitness issues of his own, but Fabregas believes Chelsea have a set of forwards that are good enough to compete on all fronts.
He said: “They are all different strikers. Diego is more powerful, Falcao is more of a finisher inside the box and I love the way Remy protects the ball, his link-up play is very good. We have three great strikers.”
Falcao was one of the world’s leading frontmen when he was at Atletico Madrid between 2011-13 but the Colombia international did not score for his new side in pre-season.
“Hopefully, he can regain his form, we will help him a lot,” said Fabregas. “If he gets his confidence back, it’s all about the ball hitting the back of the net and we will have a great, great player in our team.”
