Piotr Zielinski and a member of Napoli coaching staff, Giandomenico Costi, have both tested positive for COVID-19.
The Italian club confirmed the development in a tweet.
Napoli have begun the new Serie A season in blistering fashion, racing to the top of the table with two wins from two matches.
Zielinski has been pivotal in both of Napoli’s match this season, scoring his first goal of the campaign in the most recent 6-0 thumping of Genoa.
The Poland international will now be forced to self-isolate for the coming days.
It comes as a setback for the 26-year-old, who has been a regular in the Napoli starting lineup since joining the club five seasons ago.
News of Zielinski contracting the virus comes after Napoli’s president, Aurelio De Laurentiis recovered from the virus.
Piotr Zielinski and staff member Giandomenico Costi have tested positive for COVID-19 following Thursday's round of testing.
— Official SSC Napoli (@en_sscnapoli) October 2, 2020