Chelsea skipper John Terry could miss the next six weeks of the season after aggravating a knee injury in training.
The 31-year-old is due to undergo a small operation on his right knee on Wednesday, with early suggestions that he will not be fit until April.
Blues boss Andre Villas-Boas had hoped to have his captain available for their tie with Napoli on Tuesday evening, but he will miss the clash.
Terry will also be unavailable for England's friendly with Holland next week and will miss vital league games in Chelsea's pursuit of fourth spot in the Premier League.
