Antonio Conte defended Andreas Christensen after his mistake cost Chelsea in a 1-1 draw with Barcelona in the first leg of their Champions League last-16 clash on Tuesday.
The Premier League side had looked to be heading for victory after Willian finished brilliantly in the 62nd minute at Stamford Bridge.
However, Christensen's pass across his own box was punished as Lionel Messi scored to give Barca an away goal in the tie.
Asked about the mistake for the goal, Chelsea boss Conte said: "I think Christensen's performance was a very good performance, an incredible performance. We are talking about a player who is only 21 years old here.
"It's great that he is able to play this game with maturity and personality. I am very happy. He was one of the best players tonight.
"It is very difficult to pick one player or another player but I think Christensen played a top game. I am very pleased with his performance."
While Barcelona dominated possession, it was Chelsea who created the better chances, with Willian hitting the post twice in the first half and Eden Hazard volleying over from a good position.
"I think we were very close to playing the perfect game," said Conte. "I think we paid dearly for one mistake. But as you know very well, against this type of player - like Messi, like [Andres] Iniesta, like [Luis] Suarez - if you make a mistake you pay.
"When you play against Barcelona, we know that if we want to play against them box to box then we are crazy. You are going to lose the game. Not only 1-0 or 2-0 but like what happens in Spain, 4-0, 5-0 or 6-0.
"When you play this type of game you must use your intelligence. We know that this team now, their level is more up than us. When you have many young players, you must pay something in experience.
"For this reason, we must play an intelligent game and I repeat we are not stupid."
The return leg takes place on Wednesday, March 14, and Conte added: "It's a pity because tonight at the end of the game we are disappointed with the final result.
"At the same time I think this game must give us a lot of confidence to trust that in the second leg the qualification is open. It won't be easy because we are talking about Barcelona and also tonight they showed themselves to be a fantastic team.
"But we showed that we are ready to work very hard together. If we continue to have the right feeling that when we have the ball it is a chance to score, we can try to do something incredible at the Nou Camp.
"Tonight, I do not remember a save from Thibaut [Courtois]. They had one chance in the first half with Paulinho and in the second half with Suarez.
"I think we played a really good game. We followed the gameplan. The programme that we prepared.
"In 15 days we must be prepared for another game against Barcelona. We must be prepared to suffer together. But I repeat, we must remember that in the moment when we get the ball it is a chance to score."