Mikel Arteta says he was "surprised" Arsenal's Premier League game against Brentford was not postponed after four members of his squad tested positive for coronavirus.
Pierre-Emerick Aubameyang, Alexandre Lacazette, Willian and back-up goalkeeper Alex Runarsson all missed the Gunners' 2-0 defeat last Friday after contracting the virus.
Arteta also had to cope without several other first-team players due to injury for the opening-day loss, including midfielder Thomas Partey, forward Eddie Nketiah and defender Gabriel.
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There is no official threshold for the number of positive cases that would cause a game to be called off, but the 2021/22 Premier League handbook states "permission will not be granted to postpone a league match where the applicant club has 14 or more players listed on its squad list available".
"Yes, I was surprised it wasn't postponed, but the regulators decided the best thing to do was to play the game," the Arsenal boss said.
"What we did is what we had to do, through the club, through the club doctor as well. He explained the situation, how it developed and the risk that we consider."
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Aubameyang has since tested negative but asked whether the Arsenal captain and Lacazette will be available for Sunday's Premier League match at home to Chelsea, live on Sky Sports, Arteta added: "It's still very uncertain. I cannot give any answers today.
"I don't know if they can train in a few hours and if they are going to be able to compete at the weekend. I don't know.
"They've had some tough days. Lacazette still hasn't trained as he's not been good. Aubameyang trained yesterday but they were affected by the virus - they were ill."
The Spaniard refused to comment on claims that his players contracted the virus during a party for Aubameyang's son.
"I don't know where it came from. We can only guess where it came from," he said.
"A week before they had three or four negatives and then a positive, we have no clue where it came from."
Arsenal were heavily criticised after their defeat by Brentford, with Sky Sports pundit Gary Neville questioning the club's direction and suggesting they were "messed around" by the Premier League newcomers.
Asked why he didn't confirm the reasons for the absences of those who tested positive immediately after the game, Arteta said: "There are some policies and there are some medical privacies that I cannot forget.
"I have to protect the club and I have to protect the individuals."
Arteta also revealed the majority of his players have had both Covid-19 vaccines but stressed he would not force any of his squad to have the jab.
"Most of them have had two. Others they have had one vaccine," he added.
"We are trying to encourage them to get vaccinated because they are going to protect themselves, their families, obviously the environment around the club.
"But it is a really personal matter and we are trying to guide them and explain the reasons why it is better to do it. In the end, it's a personal decision.
"It is not about protecting ourselves, it is about protecting the people around us as well. I think it is a gesture of generosity.
"I don't know if somebody is completely convinced at the beginning to do it, but you see that the benefits at the moment are much bigger."
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