Chelsea have revealed that Pierre-Emerick Aubameyang was absent from the squad to face Manchester City on Sunday due to a small injury.
The 33-year-old was a notable omission from Graham Potter's teamsheet for the FA Cup third-round tie at the Etihad, which the Blues lost 4-0.
Aubameyang had replaced Raheem Sterling after just five minutes against the Premier League champions in Thursday's top-flight battle, although he was then taken off himself in the second half.
The former Arsenal man is now said to be suffering from a back injury, which Potter confirmed to Chelsea's social media channels after the game, adding to their ever-growing fitness problems.
Aubameyang has only recorded three goals and one assist in 16 games for the Blues since arriving in the summer transfer window, starting all six games in the Champions League but just four in the Premier League.
The Gabon international was visibly frustrated as he was taken off the field against Man City on Thursday, and his contract at Stamford Bridge only runs for another 18 months.
Aubameyang has now joined a full-capacity treatment room for the West London club, who also lost Christian Pulisic and Sterling to issues in Thursday's showdown with the Citizens.
Offering an update on the pair after the game, Potter admitted that he expected Pulisic to take "weeks" to recover, and the extent of Sterling's hamstring twinge is not yet clear.
"Christian just opened up his knee in the game the other day so we're still analysing it. It's going to be weeks I would say," Potter told chelseafc.com.
"Raheem just had an action in the first minute that game, a back heel that was a bit strange and he felt something in his hamstring. So again we are analysing that. Aubameyang had a tight back yesterday so was unable to travel."
N'Golo Kante, Reece James, Armando Broja, Ben Chilwell, Wesley Fofana, Edouard Mendy and Ruben Loftus-Cheek make up the rest of the Blues' current absentees, as Potter's side were humiliated in a 4-0 loss to Man City in Sunday's FA Cup tie.
Riyad Mahrez struck a brace alongside strikes from Julian Alvarez and Phil Foden at the Etihad, plunging Potter's long-term future at Stamford Bridge into deeper uncertainty.
However, the Chelsea boss is not fearful of a player revolt, saying: "Man City is probably the worst opponent you can play when things aren't going very well because they can make you look like you're not running or you're not trying because their positional structure is brilliant.
"They use the full width of the pitch and they keep the ball and that makes it difficult to put any pressure on them. I'm working with the players and I don't get any sense of any people with poor attitudes. Everyone wants to try and do better and there is support in the dressing room."
Chelsea will aim to bounce back from their FA Cup humiliation when they meet Fulham in a Premier League West London derby at Craven Cottage on Thursday evening. body check tags ::