Leading 2-0 after the first leg, Zidane rested most of his first-teamers and saw the visitors' Hugo Fraile and Matheus both miss excellent chances to open the scoring, before Luis Milla's long-range strike was helped to the net by fit-again Keylor Navas, shocking the Bernabeu.

Madrid had their first shot on target 50 minutes in, with defender Alvaro Tejero's long ranger easily saved. The visitors continued to have the better chances, with Navas looking sharper to stop Matheus header at the near post, and ex-Atletico Madrid defender Cata Diaz's header crashing off the crossbar.

With half an hour remaining Gareth Bale entered for his first appearance after two months out injured, and within seconds had produced a peach of a cross which was headed to the net via the crossbar by Borja Mayoral. The Welshman was involved again soon afterwards with his shot saved and Mayoral snaffling up the rebound.

The Los Blancos coach told the postgame news conference that he had expected the game to be difficult given he had rested most of his first teamers and chosen a mix of players who had much playing time recently and kids promoted from the youth team.

"I am not annoyed by the performance, just the opposite," Zidane said. "It was expected. We played a good game, better second half than first. It is not easy for the players, many of whom had not played much recently, some were youth team players.

"The most important for us is to go through in the round. Of course we can do better. We are Real Madrid, the demands are always the same, but I am happy."

Madrid were whistled off at 0-1 down at half-time against suburban neighbours making their first ever visit to the Bernabeu. Zidane said paying fans were free to give their opinions but should have taken into account that Segunda B leaders Fuenlabrada were no walkover.

"The fans can say whatever they want, they have paid their money," he said. "But the fans saw their team fight until the end, and saw players on the pitch who are new, not used to playing together.

"I am very happy with the second half we played. We were playing a team whose level was not Segunda B. They are a good unit, with very good individuals, could play easily in the second level. They played very well, had many chances."

Bale looked sharp on his comeback from two different muscle issues, while Navas and Mateo Kovacic also made their returns from injury absences.

"I am happy for Gareth, for Keylor, for Mateo who has been out a long time," Zidane said. "Navas did well, he could not do much for the [first Fuenlabrada] goal."