Chelsea forward Callum Hudson-Odoi has tested positive for coronavirus.
The Blues revealed in a statement early Friday morning that the England international had a positive test returned for Covid-19, just hours after Arsenal manager Mikel Arteta received a similar diagnosis.
Chelsea have taken steps to isolate those members of staff who have close contact with the teenager, with the club's Cobham training complex set for a partial closure.
The entire first-team squad and coaching staff will now self-isolate as a precautionary measure.
A statement read: "Chelsea men’s team player Callum Hudson-Odoi had a positive test result for Coronavirus returned this evening.
"Chelsea personnel who had recent close contact with the player in the men’s team building will now self-isolate in line with Government health guidelines.
"These will include initially the full men’s team squad, coaching staff and a number of backroom staff."
"Callum displayed symptoms similar to a mild cold on Monday morning and has not been at the training ground since then as a precaution.
"However, his test came in positive this evening and he will undergo a period of self-isolation. Despite testing positive for the virus, Callum is doing well and looking forward to returning to the training ground as soon as it is possible."
Chelsea expect those who did not have close contact with Hudson-Odoi to return to work "in the coming days".
Arsenal's league away trip to Brighton was subsequently postponed following confirmation of Arteta's positive result, with Chelsea's home match to Aston Villa on Saturday evening now severely in doubt.
The Premier League have scheduled an emergency club meeting for Friday morning and are facing calls to immediately suspend Premier League fixtures until further notice.
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