MADRID, April 7 (Xinhua) -- FC Barcelona coach Hansi Flick defended teenage winger Lamine Yamal ahead of his side's Champions League quarterfinal first leg at home to Atletico Madrid Wednesday night.

Speaking at his pre-game press conference Tuesday, Flick was asked about the 18-year-old's reaction at the end of Barcelona's 2-1 win away to Atletico in La Liga Saturday night, when Yamal did not celebrate Robert Lewandowski's winning goal and then left the pitch appearing to argue with the coach.

"He's only 18," said Flick, who added that the winger was "frustrated" after a run in which he "beat five players and almost scored."

"He left frustrated. He's emotional, and that's a good thing. I'm always going to support him," he continued, explaining that people needed to be "careful" before judging Yamal because "not everything he does is to make a fuss."

"I am always going to protect him," Flick insisted.

Atletico will field a different starting lineup Wednesday night at Camp Nou, with players such as Ademola Lookman, Julian Alvarez, Marcos Llorente and David Hancko all set to start after resting at the weekend, while injuries to Raphinha, Frenkie de Jong, Andreas Christensen and Marc Bernal limit Flick's ability to rotate his side.

The German said he hoped tiredness "doesn't affect us," but admitted he did not "have many options, because in La Liga we wanted to win and have that victory."