Chelsea manager Thomas Tuchel branded the current situation in the Premier League as a lottery as they prepared to face Wolves on Sunday.
The Blues announced before Thursday's 1-1 draw with Everton that Romelu Lukaku, Timo Werner, Callum Hudson-Odoi and the injured Ben Chilwell had tested positive while Kai Havertz missed the game because he was unwell.
"No more positive tests but the lottery starts again tomorrow morning or tomorrow afternoon," Tuchel said after watching his remaining fit players train ahead of Sunday's trip.
"We are happy at the moment that Kai has more than only one negative result so he was back in training. We left Kai out because he felt unwell and we thought there was a possibility he might be positive.
"Mateo Kovacic is back in his first training session. Jorginho is a doubt as he is in pain, Ruben Loftus-Cheek is a doubt because he is in pain. I don't know if they can play on Sunday."
The game is one of five matches that were not postponed by the Premier League amid coronavirus outbreaks.
Arsenal manager Mikel Arteta had called for the Premier League to offer more clarity on the games being postponed as it was essential to maintain fairness and Tuchel echoed those sentiments.
"It is not in my hands, but clarity and transparency is always good in every subject," Tuchel said.
"I know the rules now, I did not get involved too early. I read them and then immediately forgot them because there are so many of them."