Arsenal and Switzerland midfielder Granit Xhaka is positive for COVID-19.
Xhaka is now in isolation, after he was not with the Swiss squad for their friendly game against Greece in midweek.
The 28-year-old is away from the rest of the team, as he received a positive PCR test that was positive for the coronavirus.
According to the Swiss FA, Xhaka also has mild symptoms of the virus.
"Xhaka was diagnosed with symptoms on the morning of the game and was immediately isolated in his room," the statement from the Swiss FA said.
"A quick test turned out negative, the subsequent PCR test, carried out to be on the safe side, produced a positive result in the evening.
"Xhaka stayed out of touch with his team-mates all day. He will do another PCR test on Thursday.
"The medical staff order no further measures for the team because the other players in the senior national team are all either vaccinated or have recovered.
"A member of the staff had to go into quarantine."