The AC Milan striker said he was positive a day after testing negative for COVID-19.
"I tested negative to Covid yesterday and positive today. No symptoms what so ever. Covid had the courage to challenge me. Bad idea," Ibrahimovic wrote on Twitter.
Ibrahimovic will miss Milan's Europa League match against Norwegian club Bodo/Glimt on Thursday and the Serie A match at Crotone on Sunday.
All Milan players underwent a second round of testing on Wednesday after defender Leo Duarte was found to be positive for COVID-19 following tests the previous day.
"Zlatan Ibrahimovic has tested positive for COVID-19 following a second round of swab tests ahead of tonight's game against Bodo/Glimt," Milan said in a statement. "The club has informed the relevant authorities and the player has been promptly placed in quarantine at home. All other team members and staff have tested negative."
The 38-year-old Ibrahimovic has scored three goals in Milan's first two matches this season, in the Europa League and Serie A.
The Swedish forward set up an online fundraiser in March to help hospitals at the center of the coronavirus outbreak in Italy. He launched it with a video message which he ended by saying: "And remember, if the virus don't go to Zlatan, Zlatan goes to the virus."
