Madrid suffered their first group-stage defeat since 2012 when they were humbled 3-1 by rampant Spurs at Wembley on Wednesday night.
The result saw Tottenham qualify for the last 16 and put themselves in pole position to finish top of Group H ahead of the defending champions.
With a five-point buffer to Borussia Dortmund, Madrid still look likely to progress as well. But the manner of the loss, which came hot on the heels of Sunday's shock LaLiga defeat to Girona, has seen Zinedine Zidane's men lambasted in the Spanish media.
The headline on Madrid-based Marca, Spain's biggest-selling sports daily, read: "Sound all the alarms", with the paper adding that "Madrid's crisis in the league has transferred to Europe. Tottenham were better in intensity, speed and punch."
"SOUND ALL THE ALARMS!" – Madrid-based Marca were scathing in their assessment of Real's performance
Pais said Madrid had been left looking "groggy" and "laboured" by Spurs, with no flow in midfield, lacking a cutting edge in attack and showing cracks in defence, while the lead headline on AS – another paper based in the capital – read: "Nightmare in Wembley."
The Catalan-based newspapers of Sport and Mundo Deportivo were scathing in their analysis of Madrid's current plight, with the LaLiga champions already eight points behind Barcelona domestically.
Alongside a picture of a forlorn-looking Cristiano Ronaldo with his hands on his hips as Tottenham players celebrated in the background, Sport wrote as their headline: "Aimless."
The front cover also read: "Tottenham dance past an awful Madrid at Wembley and leave the Whiles with almost no chance of being first in the group. Madrid are in total crisis."
The paper added in its match report: "Tottenham hammered a lost team, without ideas or confidence at Wembley. The Whites suffered a severe punishment against a team who prevailed with football and faith."
Mundo Deportivo, meanwhile, said Madrid were in "free fall" following their defeat to Spurs, for whom a Dele Alli double and Christian Eriksen goal put them out of sight before Ronaldo netted a late consolation.
An editorial read: "Real Madrid in free fall after losing in London. Real Madrid not only didn't improve the image they gave in Girona, they suffered a thrashing by Tottenham.
"The Whites showed in London they are in free fall and there are no signs of an immediate reaction. In London we saw the defeat in Girona was not an accident. What happened in Girona and what happened in London is a clear sign Real Madrid are in crisis."