Samu Chukwueze scored twice to inflict a further blow on Real Madrid's title hopes as they were beaten 3-2 by Villarreal at home in La Liga on Saturday despite twice taking the lead.
Carlo Ancelotti's side had been imperious as they thrashed rivals Barcelona 4-0 at Camp Nou in the Copa del Rey semi-finals on Wednesday.
Yet they could not build on that momentum as they fell to a defeat that left them on 59 points in second place and opened the door for Barcelona to go 15 points clear at the summit if they beat Girona on Monday.
Real host Chelsea on Wednesday in the first leg of their Champions League quarter-final tie.
"It was a difficult game, we had chances and we could have made it 3-1 and slowed down the pace of the game, but it didn't happen," Ancelotti told Movistar Plus.
"We could have defended better. It was hard for us to be 100 per cent motivated."
"We have no doubts, Wednesday is a different story. The temperature has dropped a little today (Saturday), but on Wednesday it will be at full strength."
Real took the lead after 15 minutes when Marco Asensio's cross bounced off Villarreal's Pau Torres and into the net for an own goal.
Villarreal found the equaliser in the 39th minute through Chukwueze, who cut inside from the centre of the box and beat Nacho before firing low out of Thibaut Courtois's reach.
Vinicius Jr restored Real's lead two minutes into the second half with a simple finish in front of the Villarreal goal for his ninth league strike of the season.
Quique Setien's side levelled again in the 71st minute when Madrid's defence failed to clear, allowing Jose Luis Morales to fire home from close range, with VAR overturning the initial offside decision.
Chukwueze scored his second 10 minutes from fulltime with a spectacular strike from the edge of the box into the top-left corner to win the match for Villarreal and silence the home fans at the Santiago Bernabeu.
"It's a crazy goal," Chukwueze said. "It's a dream to score this goal and win here (in Madrid). I'm very happy. The future is going to be much better. I have to take advantage of this moment and keep improving."
Villarreal host relegation-threatened Valladolid next Saturday.
