Hansi Flick's side came from behind to record a 2-1 victory over Valencia in their season opener at Mestalla, before beating Athletic Bilbao 2-1 in their second game of the campaign on Saturday evening.
The title hopefuls will now finish August with games against Rayo and Real Valladolid before tackling Girona in their first fixture after the September international break.
Here, Sports Mole rounds up Barcelona's injury and suspension news ahead of their contest with Rayo, who have picked up four points from their first two games of the new season.
Ansu Fati
Status: Out
Type of injury: Foot
Possible return date: Unknown
Barcelona remain without the services of Fati, who picked up a foot injury at the end of last month; the forward has been linked with a late summer exit, but head coach Flick has said that he wants to keep hold of him.
Ronald Araujo
Status: Out
Type of injury: Hamstring
Possible return date: Unknown
Barcelona defender Araujo will be on the sidelines until the latter stages of this year due to the hamstring operation that he underwent in the middle of July.
Frenkie de Jong
Status: Out
Type of injury: Ankle
Possible return date: Unknown
De Jong has been absent since the start of March due to an ankle problem, and the Netherlands international is having to remain patient when it comes to a potential return.
Gavi
Status: Out
Type of injury: Knee
Possible return date: Unknown
Gavi is still recovering from the serious knee injury that he suffered while representing Spain towards the end of last year, but he is expected to be back on the field before the end of 2024.
Andreas Christensen
Status: Out
Type of injury: Achilles
Possible return date: Unknown
Christensen is currently on the treatment table with an Achilles problem, and it is understood that the Denmark international could be unavailable for selection until the end of October.
BARCELONA'S SUSPENSION LIST
Barcelona have no players suspended for the league clash, but Dani Olmo has still not yet been registered, so his participation in the match remains in doubt.
Khimki 
Lokomotiv Moscow 
Crvena Zvezda 
Benfica 
Feyenoord 
Bayer Leverkusen 
Spartak Moscow 
Krylya Sovetov 
Atalanta 
Arsenal 
Atletico Madrid 
RB Leipzig 
Monaco 
Barcelona 
Bordeaux 
Quevilly 
Pec Zwolle 
AZ Alkmaar 
Alaves 
Sevilla 
West Ham 
Chelsea 
Sampdoria 
Sudtirol 
Werder Bremen 
Bayern Munich 
Leicester 
Everton 
Liverpool 
Bournemouth 
Tottenham 
Brentford 
Dynamo Kyiv 
Rukh Lviv 
Juventus 
Napoli 
Rubin 
CSKA Moscow 
Voltigeurs De Chateaubriant 
Crystal Palace 
Manchester Utd 
Eintracht Frankfurt 
Borussia Monchengladbach 
Rangers 
Dundee 
Valencia 
Girona 
Vitoria Guimaraes 
FC Porto 
Rodez 
Go Ahead Eagles 
Ajax 
Reims 
Paris Saint Germain 
Real Madrid 
Espanyol 
Fiorentina 
Lazio