Napoli's Poland midfielder Piotr Zielinski has tested positive for COVID-19, the Serie A club said on Friday, five days after they hosted Genoa who have been hit by a spate of cases.
Napoli said in a statement a staff member was also positive for the virus in a round of tests conducted on Thursday.
Under Serie A's health protocol, Zielinski must go into quarantine and will miss the match at Juventus on Sunday.
He is also likely to be ruled out of Poland's friendly with Finland on Wednesday and the Nations League matches at home to League A Group 1 leaders Italy and bottom side Bosnia the following week.
Napoli are due to undergo a further round of tests before travelling to Turin for Sunday's match against the champions.
Genoa, whose game at home to Torino on Saturday has already been postponed, said earlier on Friday that two more players, Petar Brlek and Miha Zajc, and one member of staff had tested positive, bringing the total to 19 in the last week.
The club said they had suspended training until Monday.
(Writing by Brian Homewood; Editing by Ken Ferris)
