The midfielder will miss Poland’s World Cup qualifier in Hungary on Thursday while he awaits the result of a second test.
Klich could also miss Sunday’s match against Andorra, as well as the qualifier against England at Wembley Stadium next Wednesday.
The 30-year-old has not shown any symptoms or felt unwell, however.
Jakub Kwiatkowski, media officer of the Polish FA, tweeted on Wednesday: “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.”
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