Barcelona's first-team squad oozes talent with world-class players from defence to attack. But which players make the La Liga champions tick? Who is vital to their style of play?
We asked sports journalist Inigo Gurruchaga of Spanish newspaper El Pais to select his five to follow for Wednesday night.
"I choose him not only because he is a good player but also because he has a local connection. Barcelona is a combination of international stars and the local element, it gives the team local pride. Presas Oleguer is another local player Puyol stands out, he keeps the spirit and traditions of the club and I think he is a very important man in terms of the atmosphere in the dressing room and the feelings around the team."
"The holding midfield position is vital in football these days, the role that Gilberto and Claude Makelele play. Barcelona have a crucial player in Edmilson who sits in front of the back four. He doesn't get the accolades but, as Real Madrid found when they sold Makelele to Chelsea, it is a very important role he plays. You have to have the ball to be able to play and Edmilson is Barcelona's most important player when it comes to recovering possession."
"Xavi is an amazing player. There is a doubt in terms of his fitness because he has been out for a long time with a knee ligament injury, but Barcelona are not the same team without him. They have been able to win La Liga but they are less able to keep the ball and move it around with fluidity without Xavi. He was struggling for energy in the first minutes of his comeback game but, by the end of the match, he looked better. There is a big question over whether Barcelona will play him from the start against Arsenal or have him on the bench."
"I think Frank Rijkaard will try to get his team to intercept the ball high up the pitch and Deco is Barcelona's most important player when they try to do that. He is an amazingly intelligent player, he can see how the opposition come forward and try to stop them early on. He also goes forward very cleverly, he finds space and options and is so quick in his mind he seems to have a couple of seconds more than other players to make a decision."
"It's no surprise that I'm picking him. He's like Thierry Henry in a sense that, no matter who you support, you love to see him play. He plays in a beautiful way and has a wonderful attitude to the game too. Is he as vital to Barcelona as Henry is to Arsenal? I think so. He is the man who opens things up, he creates the chances. When Ronaldinho is not playing Barcelona look a bit stale, but when he gets into the action he opens defences. Few players would have spotted Ludovic Giuly's run and picked him out so perfectly in the Semi-Final against Milan. Ronaldinho drifts to the left wing, like Henry, but unlike Henry he tends to cut inside and run across the pitch, looking inside the area to see where he can play a pass."