Zinedine Zidane accepted Real Madrid's stunning Copa del Rey exit to third-tier Alcoyano will lead to further speculation over his future, but insisted he remained "very calm" over the situation.

Madrid were knocked out of the competition by lower league opponents for the first time since 2009 despite taking the lead on Wednesday, Eder Militao heading them in front on the stroke of half-time.

However, the reigning top-flight champions in Spain were unable to build on the lead, meaning an 80th-minute equaliser from Jose Solbes forced extra time.

A penalty shoot-out seemed the likely method to settle the last-32 tie, only for Juanan to pop up with a dramatic late winner that will no doubt increase the growing pressure on Zidane.

"When you lose there is always talk, I take responsibility and whatever has to happen will happen," the Madrid boss told the media in his post-match interview. 

"I am very calm. The players wanted to win the game, they try and sometimes different things happen."

Zidane rested some of his regulars but still selected a strong starting XI, while Karim Benzema, Toni Kroos, Marco Asensio and Eden Hazard were all introduced from the bench during proceedings.

The Frenchman could not fault the effort of his players as he accepted blame for the result; Alcoyano finished the game with 10 men too, Ramon Lopez sent off before Juanan's 115th-minute strike.

Madrid finished up having 26 shots - 11 of which were on target - and had 73 per cent of possession, yet still crashed out.

"The players have tried and if we score the second goal it is another match, football is like that," Zidane added after the 2-1 loss.

"The goalkeeper has made two or three saves and we have not scored the second goal, but I take responsibility. We are out."

He added: "This is football, it is very difficult because we played against a Segunda Division B team and we have to win the game, but it has not been like that.

"It can happen, it happens, these are things that happen in a football career. I assume responsibility and we will continue working. We will not go crazy."

Madrid must quickly put the cup result behind them as they continue their LaLiga title defence on Saturday, travelling to Deportivo Alaves.