Leeds midfielder Mateusz Klich has tested positive for coronavirus, the Polish Football Association has announced.
The 30-year-old will now miss Poland's World Cup qualifier in Hungary on Thursday as he awaits the results of a second test.
This could also see him ruled out of a game against Andorra on Sunday and the qualifier against England at Wembley next Wednesday.
Klich has not shown any symptoms or felt unwell.
Jakub Kwiatkowski, media officer of the Polish FA, tweeted: "The Polish national team received the results of the SARS-Cov-2 test this morning.
"Unfortunately, in the case of Mateusz Klich, the result is positive. The competitor is well and shows no symptoms of illness, but his trip to Budapest is excluded. Today the test was repeated."