Fabregas said: "People who say we are a different team without me are completely wrong. I have missed five Premier League games and except Everton, where we drew, we have won all the games.
"It is a strong squad and anyone can play at any moment.
"Right now, we have won nothing. In the league there are seven games and in the Champions League we have two games coming up. We are not thinking about being champions. We are only thinking about Birmingham.
"There is a lot of time to think about Barcelona. Our first priority is Birmingham and that is the sign of champions, taking things game-by-game.
"In the league, you can bounce back. In the Champions League, if you play bad, it can cost you. In the Champions League, we play against the best team in Europe, probably in the world.
"We are really looking forward to it. It is another opportunity to play against a great team in a great stadium. It will be very exciting.
"If you want to win this competition, you have to beat everyone. If we'd been drawn against Bordeaux or Lyon we would have taken it the same way. Barcelona are a great team but we always go with the same mentality - and that is to win.
"But first we have some important league matches."