Chelsea game a must-win - Arsenal's Fabregas
He also stressed the importance of how big a week this is for the club with the next phase of the Champions League up for grabs against Standard Liege on Tuesday.
"The Chelsea game is vital. We have to win, and we will be ready for it," the Spaniard said.
"Chelsea are a great team, one of the best in Europe, are very strong and have been playing together for a long time.
"They know each other very well, and you can see that on the pitch.
"I respect them a lot, but I know what we can do as well. If we play like we can at our best, then we can beat them.
"With the game in hand we have as well, we could still be there.
"But first of all, we think about the Liege game, and then about Chelsea, but, yes, it is an important week for us."