Only the scoreboard shows that Chelsea have the edge over Barcelona ahead of tonight’s crucial game at the Camp Nou.
Barcelona enter tonight’s Champions League match against Chelsea with a 1-0 loss from the first-leg defeat in London to overturn. The competition’s titleholders have not beaten the Blues in their last 6 meetings but only a 2-0 margin victory at the Camp Nou would do.

“We begin with a 1-0 disadvantage and we have 90 minutes to turn it around. […] I have no doubt that we will be in Munich, I have been thinking like this since the start of the season,” Barcelona coach Pep Guardiola revealed in Monday’s pre-match press conference.

“It is possible that we will have to score three goals [because Chelsea may score one]. I do not know if this [game] will be the biggest challenge since I have been a coach, but I always look at these matches with optimism because of the faith I have in these players.

“If we create the same chances that we did in London, it will be very hard for us not to score again.”

Indeed, Barcelona dominated the play at Stamford Bridge with 79 per cent of possession time and 24 shots compared to Chelsea’s 4 attempts. Portuguese midfielder Raul Meireles, who is a yellow card away from suspension, is wary of Barcelona’s threat.

The Chelsea man believes that the Catalans will do all they can to bounce back from their last two defeats in all competitions. Speaking to Goal.com, the former FC Porto key player explained:

“Barcelona’s defeat against Real Madrid could have some effect on the game on Tuesday, but it's a double-edged sword because after practically losing the league, their challenge is Europe and they will come out with even more motivation.

“The game at Camp Nou is a final for us. It's not easy to knock out Barcelona but first blood went to us and now we will have to play even more perfectly on Tuesday.”

Perfection is the word. Lionel Messi has been tipped to rock the stage with a brilliant performance tonight. The past 7 days have seen the Argentine fall behind expectations against Chelsea in the Champions League and Real Madrid in La Liga.

However, ex-Barcelona midfielder Gaizka Mendieta has backed the 3-time FIFA World Player of the Year to fire the Blaugrana into the 2011/12 UEFA Champions League final. Lionel Messi is not known to be a big-game flop and Mendieta believes this is a fact that should scare tonight's visitors.

“I know Lionel Messi has never scored against Chelsea but there is no special reason for that. He is marked closely whenever he plays,” Mendieta told Goal.com.

“It is just a coincidence. He will be very dangerous at Camp Nou [against Chelsea on Tuesday night] because Barcelona’s style is more suited to the home ground.”

Chelsea might use special tactics to stop Lionel Messi. Meireles hinted at this option when he stated:

“Messi is the number one and there is no doubt. Now we will have to make things uncomfortable for him on the pitch and not allow him time to think about his moves. It's not easy, but that's one of our missions for Tuesday.”

Pep Guardiola and his Barcelona stars are under intense pressure to save their season but they seemingly have what it takes to conquer Chelsea in the semi-finals of the UEFA Champions League. The tie is at its half point but the Blues certainly have a reason to fear a backlash from Barcelona.