Arsenal say that no-one at the club has shown any symptoms of COVID-19 after Olympiacos owner Evangelos Marinakis revealed he has contracted the coronavirus.
The millionaire businessman, who also owns Championship side Nottingham Forest, announced he was suffering from the virus on Tuesday.
“The recent virus has ‘visited’ me and I felt obliged to let the public know,” said Marinakis.
“I feel good as I take all the necessary measures and I (adhere) to the doctors’ instructions.
“I strongly advise all my fellow citizens to do the same. I wish all a quick recovery.”
Marinakis’ admission comes less than two weeks after Olympiacos knocked Arsenal out of the Europa League following a dramatic night in north London.
The Greek side beat the Gunners 2-1 at Emirates Stadium, booking their spot in the last 16 of the competition and Marinakis was at the ground watching from the directors' box.
After the full-time whistle he went down into the visitors’ changing room and was also out celebrating with the Olympiacos players on the pitch in front of the away support.
And Marinakis did have contact with numerous members of Arsenal’s staff throughout the evening - but the north London club say no-one who he was with has shown any signs that the virus may have been passed on.
"Our home match with Olympiacos in the Europa League was played on Thursday 27th February and none of our staff who came into contact with him on that matchday have reported any symptoms since,” an Arsenal spokesman said.
“We continue to follow strict protocols with regard to coronavirus. We’re following the Government health guidelines and have additional procedures in place to protect our players and staff.
“This has included regular deep cleaning of areas used by players at Emirates Stadium and our training centre."
Forest also released a statement which read: "Nottingham Forest can confirm that owner Evangelos Marinakis has tested positive for the coronavirus.
"Mr Marinakis was diagnosed after showing the first symptoms on his return to Greece yesterday afternoon. During his short stay in Nottingham last week he did not show any symptoms of the virus.
"The club are seeking advice from medical professionals and the relevant governing bodies to ensure the correct measures are taken. Until this time the club will be making no further comment."
Scientists believe it takes five days on average for people to start showing symptoms of the coronavirus.
Anyone who is symptom-free by day 12 is unlikely to develop symptoms, although they may still be infectious carriers.
Arsenal will continue to monitor the situation closely and, as is the way with anyone who has returned from one of the areas most impacted by the virus, any member of staff who shows signs of any symptoms will have to self-isolate for 14 days.