Chelsea could be without top scorer Cole Palmer when they visit Premier League leaders Arsenal on Tuesday.
Palmer is the joint-top scorer in the league with 20 goals.
However, Blues boss Mauricio Pochettino said the 21-year-old is struggling to recover from illness in time for the game.
"We will see [Tuesday] morning. Today, I don't believe he can be involved," Pochettino said.
"Even if he is good [on Tuesday] maybe he is not in a condition to play. We hope he can recover from this situation and be involved with the team."