Pena says he's delighted to be acting as Barca's No1 this season ahead of the Champions League clash.
He stated, "Obviously, you dream of playing these kinds of games. In Champions and stadiums like this. And before a team that has 27 goals in eight games.
"We will have to give our 100% to win. We are very psyched, we have been since Sunday.
"On a mental level I am the same. At the level of continuity everything adds up. The first results I had were positive and that helps on a personal and group level. I am very grateful for the trust (Hansi) Flick has given me personally and professionally.
"My game hasn't changed much either. Last year the results, Super Cup, hurt us. In Cup too. At the group level it was hard. I had to play in the decisive section of the season. I don't even remember last year. Playing games for a goalkeeper continuously is very important.
"All teams have ups and downs. No team in history has won every game of a season. Before November our level was spectacular. We know what we have done and that gives us strength to know what to do in the future. When you have demonstrated something you know you can do it. If we want to win tomorrow we have to give that level. We are going to have to be 100%."
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