Real Madrid and Barcelona take significant advantages into the second legs of their Copa del Rey semi-finals against Atletico Madrid and Real Sociedad respectively as they look to seal their place in the final on 19 April.
The two giants of Spanish football have met in each of the last three seasons in the competition, but it would be the first time since Cristiano Ronaldo's extra-time header handed Real the Cup in 2011 that they would have met in the final.
Real are first into action on Tuesday night as they travel to the Vicente Calderon defending a comfortable 3-0 lead from the first leg at the Santiago Bernabeu.
Atletico have endured a nightmare week as they followed up that defeat by losing for just the second time in the league this season against Almeria on Saturday to also surrender top spot in La Liga.
Diego Simeone's men badly missed the presence of goalkeeper Thibaut Courtois in Almeria and the Belgian remains a doubt due to a back injury.
Atletico will also be without top-scorer Diego Costa through suspension and Simeone may decide to rest a few other first-team regulars to concentrate their efforts on La Liga and the return of the UEFA Champions League with a trip to face AC Milan on the horizon next week.
Real, meanwhile, continued their fine form with a 4-2 win over Villarreal at the weekend to stretch their unbeaten run to 23 games.
Midfielder Luka Modric was again key at the weekend and the Croatian believes an away goal will be enough to kill off the tie.
"It is not finished. We need to play as if the tie was still 0-0 and like how we did in the first leg," he told Real Madrid TV. "It is important to start with confidence and not let Atletico play their football. We need to score a goal there."
Barcelona on the verge of decider
Barcelona also have one foot in the final following their 2-0 victory over Sociedad at the Camp Nou last week, although the Catalans could have completely killed the tie off after playing the final 45 minutes of that match against 10 men.
Sociedad defender Inigo Martinez is suspended as he was the man sent-off for taking his protestations towards the referee too far after he had failed to award a penalty for Javier Mascherano's last-ditch challenge on Carlos Vela.
Barcelona boss Gerardo Martino, meanwhile, is expected to make a number of changes from the side that started his side's 4-1 win over Sevilla on Sunday.
Dani Alves, Sergio Busquets and Cesc Fabregas were all rested from the start at the Sanchez Pizjuan and should return along with Javier Mascherano and Jordi Alba, who missed the Sevilla game through suspension.