Barcelona, led by Lionel Messi, will look to achieve the impossible against Bayern Munich when the two sides meet in the Champions League semifinal second leg.

Barca are staring at a 4-0 deficit after the first leg at the Allianz Arena, and with Bayern looking like the best team in Europe at the moment, they will have their task cut out to pull off an improbable aggregate victory.

"We need to score goals while playing good football," Barcelona manager Tito Vilanova said. "If we do concede, it would obviously make it much more difficult for us. The players are aware of the task at hand. We're FC Barcelona and we can't take this tie as being lost already. If we don't make it, we have to hold our heads high, fight until the end and make our fans feel proud of us.

"We can't focus all our attentions on scoring. We score goals through playing good football. We have to carry on doing what we have done until now and be better than Bayern -- plus an early goal always helps."

Vilanova is banking on Messi to deliver in the second leg, after the Argentine failed to make an impact in Germany last week, due to an injury.

"We know how important Messi is, especially when it comes to scoring goals," Vilanova added. "The better he plays, the better it is for the team. But we can't heap all the pressure on his shoulders -- the rest of the team have to help. Still, Messi will have a lot of say in the outcome."

Bayern coach Jupp Heynckes, whose brilliant tactics led to the demolition job in the first leg, is not taking anything for granted.

"I have to say Barcelona are still the best team in the world so we will prepare accordingly," he said. "They are capable of great things at Camp Nou and we want to avoid that. We will play like we did in Munich, attacking, playing to score -- let's see if it works out. We are not a defensive team, even if we do have a good defense.

"We can't think about negative scenarios. We have a very clear idea of the game we want to play and I will explain it in detail to my players. The players will give all they have and we're very motivated to reach the final. We want to prove that the match in Munich wasn't a one-off."

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Expected lineups: Barcelona: Valdes; Alves, Pique, Bartra, Adriano; Xavi, Busquets, Iniesta; Pedro, Messi, Villa.

Bayern Munich: Neuer; Lahm, Boateng, Dante, Alaba; Martinez, Schweinsteiger; Robben, Muller, Ribery; Mandzukic.

Prediction: 3-2 to Barcelona