PSG coach Luis Enrique lamented not taking their chances in defeat at Borussia Dortmund.
Niclas Fullkrug struck as Dortmund took a 1-0 lead in their Champions League semifinal after the first-leg.
Enrique said: "I think it was a very intense match, with two teams trying to do goals and pressing.
"We know each other well. We had many opportunities to score like them but they were worse at scoring.
"We didn't have this coldness in front of goal, it rarely happens that we hit the post twice in the same action but football is like that.
"We try to learn from all these things and let's think about recovering for the match in Paris which can give us the final."
PSG captain Marquinhos also said: "We made mistakes especially on the goal conceded, when the ball is exposed the defender has to run away and in games like these it's the details that make the difference. We need to be more decisive in front of goal.
"We will work this week to do better, as we have done In Barcelona, even though we are a young team, we can make up for this result."
