Chelsea is an underdog in this match and could possibly beat barca , chelsea must know the following. A messi has not scored against chelsea in the last six meetings. B chelsea must know that barca is a beatable team. C chelsea haven't lost in seven matches and it is a positive attitude. D chelsea need some luck tonight. E chelsea have tons of experience players like barca. F chelsea must mark one to one and conquer fear. G chelsea players should take note that they will play against the referee tonight