Arsenal's preparations for last week's defeat at Manchester City were hit by one of their players recording a suspected “false positive" test result for coronavirus.
The London Evening Standard says at the end of the preceding week, the player in question returned a positive sample in the Premier League's centralised testing programme and went into self-isolation, along with two of his team-mates who were deemed to have been in “close contact" with him.
Suspecting a false positive, Arsenal took samples from the player on the Saturday and Sunday and found both the antigen test for the virus and the antibody test, which shows whether a person has had the virus in the past, came back negative.
With players needing to test negative in the Premier League's programme to return to training and feature in matches, Arsenal had to wait for the players to return a negative test in the following round of centralised testing last Monday before the trio could return to training.
The trio all missed three days' training but featured in the 3-0 defeat to City.