April 21 was supposed to be the day Real Madrid ended Barcelona's reign of supremacy in Spain; rubbing salt into the wounds of Pep Guardiola's men by lifting the La Liga title at the Nou Camp.
Yet it could now be the day on which Barca reclaim the momentum in the pursuit of the league crown, as the season edges towards a potentially thrilling climax.
Only 32 days ago, Real were 13 points clear at the summit of the table, and winning the league title in Barcelona was certainly a realistic prospect.
But, following a minor blip which included three draws in three weeks, and a sensational run of form from Barca, the lead was trimmed to a mere point on Tuesday evening.
Barca's tenth consecutive league win - a 4-0 triumph over mid-table Getafe - applied extreme pressure on Real to widen the deficit to four points once again when facing Atletico Madrid on Wednesday evening.
Victory in the Madrid derby had looked far from certain for Jose Mourinho's side when Radamel Falcao cancelled out Cristiano Ronaldo's opener just before the hour, but Real eventually eased to a 4-1 win at the Vicente Calderon.
Ronaldo's seventh hat-trick of another campaign of ridiculous goalscoring feats proved to be the difference, while José Maria Callejón netted in the closing stages.
So, four points is the gap once again, and both sides must face another round of fixtures before meeting again in a hugely anticipated Clasico.
Barcelona must travel to Valencia on Saturday in order to face Levante; who continue to defy expectations in La Liga this season.
Juan Ignacio Martínez's well-drilled outfit are the team other than Barcelona to have beaten Real Madrid in the league this term, while they were drubbed to the tune of five goals at the Nou Camp in December.
Los Blancos, meanwhile, have the straightforward task of a trip to Gijon to take on a Sporting side who share the joint worst goal-difference in La Liga, along with Real Zaragoza.
A victory apiece for Spain's top two sides is seemingly inevitable, even if Mourinho and Guardiola field weakened teams with respective midweek Champions League semi-finals to attend to.
Such is the prominence given to the pursuit of glory on the continent, El Clasico has been moved forward by one day from its original date to allow extra recovery time prior to the semi-final second legs.
The period of eight days between April 17 and April 25 will prove pivotal for both Real and Barca, with both a place in the final of the Champions League and potential domestic glory at stake.
There could, of course, be another Clasico before the season's end, should Real and Barca triumph over Bayern Munich and Chelsea respectively.
Yet next weekend's encounter - the 250th in a bitter rivalry - is where the focus lies for the time being, and victory for Real is arguably more important than for Barcelona.
Mourinho has yet to get the better of Guardiola in any of the league encounters between the pair so far, with Barca recording three wins from four - including a 5-0 humiliation in the Nou Camp almost 18 months ago.
The former Inter Milan manager can, in fact, boast only one victory in ten attempts since taking the charge at the Santiago Bernabeu, and the pressure is on Mourinho to end four years without a league title for Real.
Of course, losing out to Real come the end of the season will be a bitter blow for Guardiola and his players, yet conceding defeat for just one campaign will not be seen as a catastrophe.
The profile of the Clasico has risen since Mourinho's move to Madrid, and April 21 could yet prove to be his finest hour with Real.