Maurizio Sarri says his Chelsea side are "in trouble" due to mounting injuries amid a hectic fixture schedule.
The Blues won 1-0 at Crystal Palace on Sunday and face Southampton on Wednesday in their first of seven games in January.
Sarri, though, has a paucity of options as striker Olivier Giroud suffered an ankle injury, adding to injuries for Cesc Fabregas (neck), Ruben Loftus-Cheek (back), Pedro (hamstring) and Callum Hudson-Odoi (hamstring).
"We are in trouble because, in January, we have to play every three days," Sarri said.
"Fabregas' is a neck problem. The injury was in the last five minutes of training, so I'm not sure whether he has to rest for two or 10 days."
Sarri was waiting to learn the full extent of Giroud's injury, which could alter Chelsea's January plans.
Alvaro Morata has been linked with a loan move to AC Milan, with Gonzalo Higuain moving in the opposite direction.
Higuain, who played under Sarri at Napoli, is currently on loan at AC Milan from Juventus.
There could also be implications for Eden Hazard, who had been deployed as a 'false nine' in four straight league games and could be required to play there once again.
N'Golo Kante's goal six minutes into the second half proved decisive at Palace and, not for the first time, Sarri bemoaned his side's lack of cutting edge.
Sarri added: "For 85 minutes we were in full control without conceding anything to the opponents. I didn't like only that we weren't able to kill off the match before."
Palace boss Roy Hodgson is aiming to give his side more of a goal threat by recruiting Dominic Solanke on loan from Liverpool.
"It's no secret he's a target," said Hodgson, whose side play Wolves on Wednesday.
"What would he do? Provide an attacking threat. He's a proven goalscorer through all the age groups at (former club) Chelsea and England.
"If he comes here, it'll be up to him to show he can do that in Premier League football.
"He's someone with the profile we're looking for, and the ability we are looking for."
