The European champions thrashed Real 4-0 to set up a final with Chelsea this weekend. PSG were 3-0 ahead before halftime through a double from Fabian Ruiz and Ousmane Dembele, before Goncalo Ramos struck late in the second-half to complete the rout.
At the final whistle, Courtois conceded: “They always start very strong and with a lot of pressure high up. We failed to follow the coach's plan of looking for space up front. We struggled to hold our position and they found the free man very well.
"They created a lot of danger, especially in the first half. In the second half, they stopped pressing and we had more chances, but we didn't score. The first two goals killed off the game a bit and they were comfortable."
He added, “It's a tough defeat, but a defeat to learn from. We’re on the right path and sometimes a setback like this is good for you to keep improving, to know that there is a lot of work ahead and that we can get better. We have to reach their level, they have won the Champions League and they've been very good in this tournament. We have to work on next season.”
We need to analyse this defeat
Asked why coach Xabi Alonso's game plan failed on the day, Courtois also said: “This is something that needs to be analysed in the video. From my point of view, we were a bit off the pace. The moment you are late, everybody is out of position.
"At speed, they beat you because they go forward and you have to turn and you lose time. We were not very close to them and that was the problem.
"When you're spread out on the pitch and with so much space, against a good team like them, it's difficult.”