On Sunday, it was officially confirmed that Sergio Busquets had contracted Covid-19.
The Barca player left the national team in an ambulance and went home to self-isolate despite showing no symptoms, according to Mundo Deportivo.
5 other Spanish players are said to be self-isolating. They train individually.
On Tuesday, Lithuania will take on Spain U21 instead of Luis Enrique's side in a friendly game.
On Thursday and Friday, Busquets will take the PCR tests to find out whether he'll be able to play at Euro 2020.
Of course, the test results of those training individually matter too. If something goes wrong, Luis Enrique may be forced to replace the Covid-infected players before the tournament kicks off.
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'You're called up, 25 on the list!': Mics pick up Luis Enrique's words in emotional meeting with Ansu Fati
Ansu Fati has been invited to watch Spain's training session ahead of their friendly game against Portugal on Friday.
Here's what Luis Enrique told the youngster as he saw him for the first time in many months, as per Diario Sport.
"YO! ANSU! You look strong, you're in shape! You're called up, there are 25 of us on the list! We're keeping your seat at the table. What a haircut!"
Of course, Lucho's words about Ansu's call-up are just a way of encouraging the lad but it's quite special that the coach actually left two free slots in his Spain squad for Euro 2020.
Ansu Fati will reportedly be back to play for Barca in six weeks' time which means he should be ready to feature for the Blaugrana during the preseason if all goes well.
The 18-year-old was forced to miss the bulk of Barcelona's 2020/21 campaign after suffering the injury back in November.
No Real Madrid players for first time in history as Luis Enrique unveils Spain squad for Euro 2020
Luis Enrique has unveiled his Spain squad for the upcoming Euro 2020.
Jordi Alba, Sergio Busquets and Pedri have all made the cut.
Barca's reported targets Eric Garcia and Jose Gaya are in the squad as well.
Surprisingly, there are no Real Madrid players on the list – even Sergio Ramos is out. This happens for the first time in football history.
Goalkeepers: Unai Simon, David De Gea, Robert Sanchez.
Defenders: Jose Gaya, Jordi Alba, Pau Torres, Aymeric Laporte, Eric Garcia, Diego Llorente, Cesar Azpilicueta, Marcos Llorente.
Midfielders: Sergio Busquets, Rodri, Pedri, Thiago, Koke, Fabian Ruiz, Olmo.
Attackers: Mikel Oyarzabal, Alvaro Morata, Gerard Moreno, Ferran Torres, Adama Traore, Pablo Sarabia.
