The Pole credited the approach of coach Hansi Flick for the win.
He said afterwards: "Since the beginning of the season we have had one objective: we have to play very offensively but in the end the defensive line plays very well. Everything that works so far is almost perfect. We have to look at what we can do better.
"I feel very good, we are very happy. I think that in this Champions League phase, away games are very important. From the beginning we wanted to score. In the first half we played a little bit slowly but in the second half we had many opportunities.
"Sometimes when a team plays very defensively like Red Star today, I need a bit of patience. I am always looking for an open space so I can touch the ball and score. That's why I am very happy. As a team we played very well."
Inigo Martinez was also on the scoresheet and said: "Things are going very well. Other times they are not, especially when the team loses intensity. That's when the team suffers. If we improve that, we will be a great team. Now we can enjoy the victory, we are very happy.
"The play was pre-rehearsed (for my goal). We knew they were suffering at the far post. When I saw it coming, I could have scored the goal. We all like to contribute to the team."