Arsenal's Community Shield plans have been hit by up to four players reportedly returning late to training after self-isolating.
Mikel Arteta's FA Cup winners face Premier League champions Liverpool in Saturday's traditional curtain-raiser to the season at Wembley.
But Gunners boss Arteta says "it’s not an ideal moment to play", with some of his players having been in quarantine.
Goalkeeper Emilano Martinez, who impressed during the restart after Bernd Leno's injury, has been self-isolating following a holiday in Portugal.
The Argentine is free to play on Saturday after his quarantine period ended - however he was forced to return late to pre-season training, and could find he has lost his place to Leno.
Another player self-isolating is imminent signing Gabriel Magalhaes, according to The Sun.
The publication says Gabriel is in quarantine in the UK as the 22-year-old centre-half waits to complete a £25million transfer from Lille.
Two more unnamed players are also self-isolating, according to Mail Online.
The new Premier League campaign does not start until September 12, with last season having only concluded in July due to the coronavirus pandemic.
Arteta suggested this weekend was not the best time for the Community Shield clash, which normally takes place a week before the league campaign begins.
“We’ve been through all the different moments with the restrictions and rules from the government and Premier League testing," said the Arsenal boss.
“It’s all so unexpected what is going to happen from day to day.
Should Mikel Arteta play Emiliano Martinez or Bernd Leno on Saturday? Have your say here
"But we are trying to adapt and to get the team in the best possible shape to compete on Saturday.
“We’ve only had two training sessions and this game comes right in the middle of our mini pre-season, so it’s not an ideal moment to play."
With Martinez having returned late to training, Leno could get the nod to play in goal on Saturday, having fully recovered from a knee injury.
