Barcelona coach Luis Enrique believes his side have what it takes to score six times against PSG and overcome a 4-0 first-leg deficit.
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The Catalan side was hammered 4-0 in the first leg at the Parc des Princes, but Luis Enrique has not given up hope of staging a dramatic comeback.
"We are only halfway through the tie," the outgoing Barcelona coach told a news conference. "There are 95 minutes left and lots of things can happen.
"I go into the game with a positive mood. We have to do everything really well, both in defence and in attack. PSG are a really good side.
"Of course, lots of things have happened since the first leg. We have improved and have put in some good performances. We are optimistic by nature and convinced of what we can do. We will try to make the most of the favourable circumstances.
"If a team can score four times against us, we can score six times against them. We have seen that before this season. We have nothing to lose.
"My optimism does not mean I have unbreakable faith, but there are all sorts of performances in sports, negatives and positives. We have not been in a situation like this before, but I have faith in the team. You always have to keep your emotions in check.
"I am not interested in becoming part of history. But I am convinced we will get chances. That does not mean it is definitely going to happen, but I think we can get close and boost morale even further, which could affect our opponents.
"I don't have the feeling that we need the best game since I got here. We obviously have to play well and really effective. But it depends on how the match goes.
"Penalties on the training pitch are nothing like penalties in a big game. We have not trained penalties. I am not worried about penalties."
Barcelona will need star player Lionel Messi to be at his very best if they are to turn things around, but Luis Enrique is adamant it is all about the team effort.
"I look at all my players and they all have the attitude necessary," he added.
"I know everybody likes to focus on Messi and he is a point of reference who can make the difference, but this is going to be a team effort. The team effort is what matters."