Djourou, Laurent Koscielny, Bacary Sagna and Gael Clichy will be charged with one of the most difficult tasks in world football at the Emirates Stadium when they try to frustrate Lionel Messi, David Villa, Andres Iniesta and Xavi.

That world-class quartet have combined to devastating effect this season as Barca reduced defences to rubble across Europe.

Arsenal have already had first-hand experience of Barca's brilliance after losing 6-3 on aggregate to Pep Guardiola's team in the Champions League quarter-finals last season.

But Swiss centre-back Djourou hasn't been losing any sleep about stopping Messi and company because he believes the Gunners are now good enough to rise to the challenge.

"We all know about Barca, they are a great team. We know about Messi but it is not only about him. There is Xavi and Iniesta as well," Djourou told reporters here on Tuesday.

"We all know what they do, we watch the games. But you don't get scared, if I was scared I wouldn't be playing.

"Messi is just a great player, he has showed that across the world, but I am excited. It is a team game and as long as we have cover we will be hard to beat.

"We have to be focused as a group and get behind the ball. It is not just about the defenders, we have to block the space as a group."

Arsenal looked a little in awe of Barca when they met last season, but the young Gunners have grown up over the last 12 months and Djourou believes his team will show they are now capable of beating the best.

"Every game is a big game, I don't see it as bigger because it is Barcelona," he said.

"They are the best team in the world but for me and the team it is a normal game. We want to be focused and go through.

"It could show we have great ability not only in the Premier League but also in Europe. We could show the world that Arsenal is a big club."

Arsenal's defence has often been seen as the team's weak point but Djourou - back in the team after a serious knee injury - and young goalkeeper Wojciech Szczesny have made the Gunners a tougher unit to break down.

Szczesny will be making his Champions League debut after coming into the team in December following an injury to Lukasz Fabianski.

The 20-year-old Pole spent much of last season on loan at League One Brentford before making his Premier League bow in a 1-0 defeat at Manchester United in December.

He impressed Wenger enough to retain his place and Djourou is confident he will be able to handle the pressure of playing in the biggest match of his life.

"He is not scared, if he needs to say something he will. If a goalkeeper is confident and comes out for crosses, it gives you more confidence," he said.

"He does shout, he is very loud, he has got a good presence, for a guy his age, he looks like he has been playing for a long time."