Diego Llorente has become the second Spain player to test positive for COVID-19, less than one week out from their Euro 2020 opener.
The Royal Spanish Football Federation (RFEF) confirmed the news on Tuesday following the latest PCR tests within the squad.
Spain's Euros preparations were thrown into chaos when captain Sergio Busquets returned a positive coronavirus test on Sunday, forcing the entire team into isolation and Tuesday's friendly with Lithuania to be hastily re-arranged.
Leeds United defender Llorente has since left Las Rozas in a medicalised vehicle, following all health protocols, while the national team will continue with personalised training.
The remainder of the senior squad in isolation all returned negative tests but will continue to follow strict protocols before the start of Euro 2020, with Spain scheduled to open their tournament against Sweden on Monday.
"The RFEF regrets to announce that central defender Diego Llorente has tested positive in the last PCR tests carried out this morning at the national team camp in Las Rozas," the statement read.
Spain head coach Luis Enrique has created a parallel training bubble with stand-by players, including Rodrigo Moreno, Pablo Fornals, Carlos Soler, Brais Mendez, Raul Albiol and Kepa Arrizabalaga
The Spain Under-21 squad represented the side in Tuesday's friendly with Lithuania, winning 4-0.
Spain have been drawn in Group E, alongside Sweden, Poland and Slovakia.