Barca beat Las Palmas in a hard-fought match on Saturday and after their 2-1 win in Gran Canaria, goalscorer Luis Suarez said: "These are the games that win you league titles."
And 24 hours on, those seemed like wise words. While Barca came through their tough test, Madrid flunked theirs with a 1-1 draw at Malaga. It was Zidane's third away match in La Liga, all in Andalucia, and those have yielded one last-ditch win (at Granada) and two ties (at Betis and Malaga). Simply not good enough.
Madrid have not won La Liga since Jose Mourinho's second season in Spain in 2011-12. The Portuguese's successor Carlo Ancelotti then claimed four trophies including the Champions League, yet failed to bring back the Primera Division title to the Santiago Bernabeu in his two campaigns in charge and there will be no championship this time around either.
The title triumph in 2011-12 is Madrid's only Liga win in the last eight years and in that same period, Barca have claimed the Primera Division no less than five times (three under Pep Guardiola, one with Tito Vilanova and another coached by Luis Enrique). And the Catalans are well on course for a sixth in the current campaign.
Barca lead Madrid by nine points and even if Real were to draw level, it would be insufficient unless they were able to thrash the Blaugrana at Camp Nou in the Clasico clash in April and overturn the goal average from their 4-0 loss at home to the Catalans in November.
With just 13 fixtures remaining, it is mission impossible and Atletico are also adrift after the weekend action. Diego Simeone's side were held at home by Villarreal in a goalless game on Sunday and are now eight points off the top. Having lost both home and away to Luis Enrique's men, they too would need to beat Barca's points haul to claim La Liga. It's a tough ask to say the least.
For Madrid, it is yet another failure in a desperately disappointing season. Thrown out of the Copa del Rey for fielding the suspended Denis Cheryshev against Cadiz, Real parted company with Rafa Benitez in January and Zidane claimed he would fight for the two trophies on offer.
But several weeks later, only the Champions League is realistically left and the team's troubles in La Liga over recent seasons represent a sorry state of affairs for the world's richest club.
Against Malaga, Cristiano Ronaldo headed the visitors into the lead and Madrid were somewhat fortunate because he had been in an offside position when the Toni Kroos cross came in. And minutes later, the Portuguese saw a penalty saved by Carlos Kameni in a miss that proved to be costly as Raul Albentosa levelled in the second period and Real had no reply.
Asked afterwards if La Liga is lost for Madrid, Zidane said: "Not at all. It will be difficult because we dropped two points but we will never give up. There are 39 points left. We had a difficult game and we could even have lost. You (the journalists) think La Liga is lost, but neither myself nor the players think that."
It was the right message, but surely not even the most optimistic of fans really believe this stuttering side can make up 10 points on Barca in the final 13 rounds of the championship. There is just no way it will happen.
"We have to be positive because all of the games we have played up until now have been phenomenal," Zidane added.
Whether fans and president Florentino Perez will agree with that assessment is unclear, but the truth is the Frenchman has come in mid-season with limited coaching experience to try and lift a team already struggling under Benitez.
That was never ideal and the 43-year-old needs to be given time to try and turn this situation around. For now, however, it's the same old story for Real Madrid: another season, another disappointment in La Liga - and another reason for Florentino to take a long, hard look at this faltering project.