Chelsea could play their Premier League game against Crystal Palace without key midfielders Enzo Fernandez and Moises Caicedo, manager Mauricio Pochettino said.
Chelsea, who were 10th ahead of the Boxing Day fixtures, were already without Raheem Sterling and Cole Palmer – two of their top three scorers – for the London derby on Wednesday due to suspension.
Although Fernandez is recovering from a hernia, Caicedo is ill and nine players are injured, leaving Pochettino without 11 players for the final home game of the year.
Noni Madueke and Romeo Lavia are available after they returned from injury in Chelsea's loss to Wolverhampton Wanderers on Sunday.
"No, Enzo no. But Mo (Caicedo), hopefully yes. Today he was better, yesterday (Saturday) he was a possibility – but it's a high fever. I hope he can train a little bit and be ready for Palace," Pochettino told reporters.
"With Lesley (Ugochukwu), we will assess him tomorrow, but I think he felt his hamstring again. I said in the press conference it is important how we reintroduce players, but we were forced because of the problem with Moises to play Lesley."
Madueke and Mykhailo Mudryk are expected to start and Christopher Nkunku could make his full debut against Palace.
Chelsea have received a league-high 56 yellow cards but when questioned about the club's disciplinary record, Pochettino defended his young squad.
"It's representative of the fact that we play for Chelsea, we are a big club and you feel the pressure," he said.
"When you are frustrated and lack a bit of experience, it's somewhere we can improve,. It's Palmer's first season in the Premier League and it is normal. He is playing for Chelsea. Of course, it's frustrating.
"But the players care, the players want to win. It's not about a lack of discipline, it's about having the ability to read the situation of the game."