Blaise Matuidi's equaliser with the last kick of the first leg left the quarter-final tie balanced at 2-2 and despite Barca's away goals, Brazilian Leonardo remains hopeful.
"We are very, very proud," he told the club's official website.
"I am not just talking about the result, I am proud of the players' performance.
"Yes, it will be difficult in Barcelona, but you never know. Anything can happen in football."
PSG trailed to Lionel Messi's wonderful first-half strike and again to Xavi's late penalty, but hit back on each occasion as Zlatan Ibrahimovic scored their first goal from an offside position and then teed up Matuidi for the second.
Coach Carlo Ancelotti added: "It was a good match, and difficult. We wanted to play and we did that well in the first 30 minutes.
"Once we conceded the goal, we were chasing the game and that was sometimes tricky. It will not be easy, we have to win over there."
Matuidi's impressive performance was soured by a yellow card which means he will be suspended for next Wednesday's return leg, a decision Ancelotti felt was "not merited".
And the France midfielder said: "I am happy to have scored but I am suspended for the return match. I am very disappointed but I have confidence in my team-mates, we will support them in the hope they can repeat the same performance."
"We played well against the best team in the world. We played with heart and we are happy to have equalised late on. The crowd were magical.
"Sadly we conceded two goals. It will be very hard at their ground in the return match, but in football anything is possible. We will do all we can to qualify."