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.”
Chelsea are ninth in the Premier League – three points off seventh place – and Palmer’s absence would be a blow for their hopes of qualifying for Europe.
However, it would be a boost to Arsenal’s aspirations of winning the Premier League for the first time in 20 years.
The Gunners’ hopes were dented by a 2-0 loss at home to Aston Villa on 14 April but they recovered with victory by the same scoreline at Wolverhampton Wanderers on Saturday.