Kepa Arrizabalaga has been added to Spain's parallel training bubble after Sergio Busquets' positive Covid-19 test.
Spain pulled out of their final Euro 2020 warm-up game with Lithuania on Tuesday after the Barcelona midfielder contracted coronavirus and are set to field an under-21 team in the match.
Along with Kepa, Leeds United forward Rodrigo Moreno and West Ham midfielder Pablo Fornals have also been called into the bubble.
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The Chelsea goalkeeper becomes the sixth player to be added to Spain's training bubble after Valencia’s Carlos Soler, Brais Mendez of Celta Vigo and Villareal’s Europa League-winning defender Raul Albiol.
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The players on standby will not stay at Spain's Las Rozas training base or be involved with the rest of the squad but will be called on should there be a Covid-19 outbreak in the main squad.
The Spanish FA said on Monday that all players and staff currently isolating have tested negative.
Spain's Sports Minister Jose Manuel Rodriguez Uribes told Cadena Ser radio station that Spain's players will receive a Covid-19 vaccination on Wednesday.
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He said: "We are making an exception because they represent us in a top-level competition."
Luis Enrique’s side begin their Euro 2020 campaign against Sweden in Seville on Monday followed by Poland on 19 June and Slovakia four days later.
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