Barcelona legend Carles Puyol remembers 2012 Barca match against Chelsea
"The difference is that we lost 1-0 in London so we had to win. We went out to attack and were 2-0 up, after that they made it 2-1. We did all we could to score another goal but Fernando scored the second on the counter attack and eliminated us.
"Now I think Chelsea will play a similar game: very strong in defence and look for counter-attacks. For Barcelona, the advantage they have is that with the 1-1 draw they will go through with a 0-0.
"After the first leg I think Barcelona are the favourites but you can't be sure. Chelsea have shown that they are a very organised team with clear ideas about how they want to play and players up front who are very dangerous and very quick.
"They can hurt you a lot on the counter attack so Barcelona will have to put in a serious performance and try to score a goal because if they don't Chelsea could hurt them on the counter."