Manager Carlo Ancelotti praised Real Madrid's youngsters after they helped the team to a 3-2 win at Leganés -- with Gonzalo García, 20, scoring a 93rd minute winner -- in the Copa del Rey quarterfinals on Wednesday.

A much-changed Madrid side, which included young defenders Raúl Asencio, 21, and Jacobo Ramón, 20, as well as attacking players Arda Güler, 19, and Endrick, 18, went 2-0 up at Butarque thanks to goals from veteran Luka Modric and Endrick, before a brace from the hosts' Juan Cruz tied the game at 2-2.

Garcia -- who has scored 19 league goals for Madrid's reserve team Castilla this season -- then came off the bench to head the winning goal from Brahim Díaz's cross, to assure Madrid of a place in the semifinals.

"It was an even, competitive game. We suffered at the back. Jacobo was a bit nervous at first, and then he started to get things right. Gonzalo is in good form for Castilla. We have to be happy with what the youngsters did," Ancelotti said in his post-match news conference.

"They can make mistakes, but they contributed to the team. We need them, it's a difficult moment. We have to get through it with games like today, where we suffered."

A defensive injury crisis has left Madrid without all three of their senior centre-backs -- Éder Militão, Antonio Rüdiger and David Alaba -- at an important stage of the season.

Real host local rivals Atletico Madrid at the Santiago Bernabéu in LaLiga on Saturday, before visiting Manchester City in their Champions League knockout round playoff first leg.

"Those who work below us [in the academy] are doing well, creating players who are well prepared," Ancelotti said. "There's Raul [Asencio], Gonzalo, and Jacobo, who's had a long injury. For three months, he couldn't play. He's still lacking something. But we're aware that we can count on them."

Ramón was making his first start of the season, having appeared as a substitute in Madrid's 5-1 win over Salzburg last month, and had some nervous moments, including conceding a first-half penalty.

"Jacobo isn't the player who played today," Ancelotti said. "He's a very good player, a good defender. He'll be with us until the end of the season. He'll play better than today, I'm convinced of that."

Ancelotti admitted his team selection against Leganés had been conditioned by Madrid's upcoming fixtures.

"We took into account the next two games, obviously," he said. "[We didn't want] to tire the team too much, because we have an emergency at the back. We have to give the youngsters we have -- Arda, Endrick, Jacobo -- minutes to find their rhythm, so they can be useful in the coming games."