Real Madrid can transform their own season by beating Liverpool in this month's Champions League final, and on Sunday they can dent Barcelona's by becoming the first team to defeat the Catalans in La Liga.
This 'clasico' at Camp Nou will have minimal impact on the league, with Barca already crowned champions and Real's passing interest in pipping Atletico to second place diminished by their ambitions in Europe.
But there is still much at stake in what Madrid's daily newspaper Marca has billed "the clasico of honour". It could even be argued this match will go some way to defining the seasons of these two teams.
Barca, in particular, have been careful in celebrating their domestic double, their players aware of the disappointment that lingers from their Champions League crash in the quarter-finals.
Even as they ordered pizza and slurped beer from the top of their open-top bus down Las Ramblas this week, it was noticeable how many interviews still referenced the disappointment in Rome.
"The elimination in the Champions League, it hurt us because it was unexpected," said Barca coach Ernesto Valverde. "But it is very difficult to do what we have done and now what are we going to do? We keep trying."
To soften the blow, Barca's best response was to win the Copa del Rey and La Liga and finish unbeaten in the league for the first time, while hoping Real do not go all the way in the Champions League. The latter two are still to be decided.
Real's march towards a 13th European triumph has certainly weighed heavily on Barcelona, whose sense of absence has been heightened by the progress of their rivals.
"It's amazing to be in a Champions League final for the third time in a row and have the chance to win it for the fourth time in the last five years," Real midfielder Toni Kroos said on Tuesday.
"It's hard for me to find words to describe that. When it comes to the Champions League, we have extra motivation."
Barca are looking to avoid defeat this weekend, and in their last three league games against Villarreal, Levante and Real Sociedad to seal a historic season.
But if Real snatch a victory at the Camp Nou and also see off Liverpool, perhaps the balance is tipped in their favour.
It will certainly be the last 'clasico' for Andres Iniesta as a player while Gareth Bale may also wave goodbye to this fixture, with the Welshman expected to consider his future at Real in the summer.
The suggestion is both teams could give the departing Iniesta, Barca's captain, a guard of honour, even if Real refuse to do so for Barcelona's La Liga triumph.
Bale was again a substitute against Bayern Munich on Tuesday, meaning he has now started only one of Real's six Champions League knock-out games.
Zidane has been playing Bale, and resting key players, in La Liga matches but he is not likely to field a weakened team this weekend.
Elsewhere, Sevilla will play their first match under their caretaker coach Joaquin Caparros on Friday against Real Sociedad.
Vincenzo Montella was sacked after last weekend's loss to lowly Levante, which left the team eighth in the table and a point outside the Europa League qualification places.
"We have changed some subtle things but there is no time," Caparros said on Thursday. "Our work with the players so far has been more than anything emotional."
Atletico Madrid, who are five points ahead of Real, host struggling Espanyol on Sunday.
Fixtures (all times GMT)
Sevilla v Real Sociedad (1900)
Girona v Eibar (1100), Athletic Bilbao v Real Betis (1415), Celta Vigo v Deportivo La Coruna (1630), Villarreal v Valencia (1845)
Malaga v Alaves (1000), Atletico Madrid v Espanyol (1415), Las Palmas v Getafe (1630), Barcelona v Real Madrid (1845)