“Ashley Young tested positive for Covid-19 following the tests carried out yesterday (Saturday) at Appiano Gentile,” the club said in a statement.
“The English player is already in quarantine at home.”
Former Watford and Aston Villa player Young joined Inter from Manchester United in January.
The 35-year-old becomes the sixth player to test positive at the club after midfielders Radja Nainggolan and Roberto Gagliardini, defender Milan Skriniar, Italy under-21 international Alessandro Bastoni and goalkeeper Ionut Radu.
Serie A runners-up Inter Milan next meet city rivals AC Milan on October 17.
The derby remains in doubt with two Milan players defenders Leo Duarte and Matteo Gabbia currently in self-quarantine.
Milan’s Swedish star Zlatan Ibrahimovic returned to training on Sunday after two negative swabs, having tested positive on September 24.
AC Milan are second in Serie A after winning all three of their games, with Inter Milan fourth after two wins and a draw.
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