Barca took control of their quarterfinal with this first-leg win via goals from Lamine Yamal, Raphinha and a Robert Lewandowski brace.
Flick said, "Both things are important. We played very well, and that's the most important thing. When you play like that, you end up scoring goals, which is what happened.
"Not yet (is Barca into the semifinals), no, no, no... you never know what might happen. Football is a crazy sport. In Dortmund, we have to play like we did today. They're a very good team. We have to have confidence and make as few mistakes as possible."
On Yamal's substitution, he said: "Yes, he's fine. He had played too many minutes. We have a very good relationship. First, he told me he wanted to play the whole game, and then, he didn't. Ansu would have played anyway; he deserved it."
Indeed, Fati came on to replace Yamal and Flick also said: "It was good that Ansu was able to play. He deserved to play. It's important for him to get minutes. He's training very well and deserved to play. I've spoken with him a lot and told him what I expect from him, and he's conveyed that in recent weeks. I never promise anyone minutes; you have to keep in mind the game, which dictates the substitutions. He's done really well."
On Raphinha's performance, Flick concluded: "Our way of understanding football is to fight until the end. That benefits the team. Pressing against the opponent's possession... it's important that everyone gives their all. Keeping the ball away from the goal. I thought he was an extraordinary player; he's shown that throughout the season. He's a role model. He confirms my first impression. He puts the team on his back."