Manchester United forward Jesse Lingard is isolating after the club confirmed he has tested positive for Covid-19.
The England international will sit out Saturday's pre-season friendly against Everton.
Manchester United start their Premier League campaign against Leeds at Old Trafford next Saturday.
Ahead of the Everton friendly, a United statement read: "Unfortunately, Jesse Lingard is unavailable after testing positive for Covid-19.
"He is isolating in line with Government and Premier League Guidelines."
Lingard appears set to see more regular action for United this season, after he was sent on loan to West Ham last January.
The 28-year-old made a huge impact with the Hammers, helping them to finish sixth in the table.
A starter in the 2018 World Cup semi-final, he also forced his way back into the England squad - although he was not selected for the Euro 2020 finals.
United say Harry Maguire, Luke Shaw and Anthony Martial will all start in front of 55,000 fans at Old Trafford this afternoon.
David De Gea, Victor Lindelof, Bruno Fernandes and Paul Pogba were back in training this week and could also feature at some stage.