Chelsea have yet to make any comment following Ghanaian claims that midfielder Michael Essien will be out for at least a month.
Essien is reported to be out of the African Nations Cup after suffering a knee injury in training.
The Chelsea star is also likely to miss crucial Barclays Premier League and Champions League games after scans are understood to show that Essien has suffered a partially torn medial collateral ligament in his left knee and damage to his meniscus.
Ghana’s team doctor believes the 27-year-old will be out of action for at least a month.
“This is a big blow because Michael is so important to our team,” said striker Matthew Amoah. “We’ve lost the motor in our midfield, and this is very bad."
“Michael was turning to make a pass when he just went down,” midfielder Anthony Annan told BBC Sport.
“There was no contact from any other player but those around him say they heard a click, and then the physios rushed over.”
Essien was taken to hospital in an ambulance and underwent a scan in Luanda on Sunday.
His loss will be a bitter blow to Carlo Ancelotti, although the Italian coach had to play through most of December without Essien.
The midfielder has not played for Chelsea since he sustained a hamstring injury. His recovery from the setback prevented him from joining-up with his international team-mates on time.
Chelsea face Arsenal in the Barclays Premier and Inter Milan in the Champions League next month and Essien is unlikely to play in either if his injury is confirmed by the club.