Hansi Flick's side have beaten Valencia and Athletic Bilbao in their opening two games of the new season, while an impressive start from Rayo has seen the capital outfit pick up four points from their two fixtures.
Match preview
Rayo picked up an excellent result in their opening game of the new season, recording a 2-1 victory away to Real Sociedad, before sharing the points with Getafe in a goalless draw last time out.
A return of four points from two matches represents a strong start for Inigo Perez's side, who now have back-to-back home games against Catalan teams Barcelona and Espanyol, with their first match after the upcoming international break taking place against Osasuna on September 14.
Los Franjirrojos have finished 12th, 11th and 17th in their three La Liga campaigns since returning to the top flight, and they were only five points ahead of the bottom three last season.
Perez's side have managed to boost their squad with the signings of five players this summer, while there have also been five exits, with the biggest of those proving to be Andres Martin to Racing Santander.
Rayo have enjoyed their recent meetings with Barcelona, triumphing in three of their last six games in La Liga, suffering just one defeat in the process, which proved to be a 3-0 loss in their last meeting back in May.
Barcelona, meanwhile, have also made a strong start to the season, opening their campaign with a 2-1 success over Valencia on August 17, before beating Athletic by the same scoreline on Saturday night.
Much of the pre-match talk had been surrounding Nico Williams, who has rejected the chance to join Barcelona to stay with Athletic, but Lamine Yamal and Robert Lewandowski were both on the scoresheet for Flick's side to ensure that the title hopefuls made it six points from their opening two matches.
Off-the-field, there remain issues, with the club scrambling to move players on in the latter stages of the market in order to ensure that Dani Olmo and any potential late arrivals can be registered, but it has been a strong start to the season from the team, with Lewandowski in particular impressing.
Barcelona actually failed to beat Rayo in five La Liga matches between October 2021 and November 2023, and the last game between these two teams in Madrid finished in a 1-1 draw last November.
The Catalan outfit will know that the margin for error this season is small due to the excellence of Real Madrid, though, and they will enter Tuesday's match as the strong favourites to triumph.
Rayo Vallecano La Liga form:
Barcelona La Liga form:
Team News
Rayo will again be missing Andrei Ratiu due to a muscular problem, but the home side are otherwise in strong shape for Tuesday's game, and there are not expected to be many surprises in the side.
That said, due to the relatively quick turnaround, it is likely that the team will be freshened, so Isi Palazon could be introduced in the number 10 position, with Oscar Trejo potentially dropping down to the bench.
Sergio Camello, meanwhile, is likely to be brought into the side as the centre-forward, with Randy Nteka expected to be taken out of the XI after back-to-back starts in 2024-25.
As for Barcelona, five players will miss the contest through injury, with Andreas Christensen, Ansu Fati, Ronald Araujo, Frenkie de Jong and Gavi all unavailable for selection.
Head coach Flick has admitted that he 'does not know' whether new signing Olmo will be registered in time, but even if the club are successful, the Spaniard is unlikely to start due to his lack of matches.
There may be just the one change to the side that took to the field for the first whistle against Athletic, with Fermin Lopez, who is back after his exertions for Spain at both Euro 2024 and the Olympics, replacing Ferran Torres.
Rayo Vallecano possible starting lineup:
Cardenas; Balliu, Lejeune, Mumin, Espino; Valentin, Ciss; De Frutos, Palazon, Embarba; Camello
Barcelona possible starting lineup:
Ter Stegen; Kounde, Cubarsi, I Martinez, Balde; Bernal, Pedri; Yamal, F Lopez, Raphinha; Lewandowski
We say: Rayo Vallecano 0-1 Barcelona
Rayo deserve huge praise for a solid start to the campaign, and the capital outfit have certainly shown in recent years that they can cause Barcelona issues. We are expecting Tuesday's affair to be tight, but Barcelona have enough quality to make it three straight wins this term.