Didier Drogba is to undergo surgery as part of his recovery from the groin injury that saw him depart early from Sundays game against Liverpool.

The loss of the Ivory Coast striker who has begun every game so far this season, is a blow to Chelsea coach Jose Mourinho.

“He has an injury that the medical department found the best way to solve will be with a little surgery, but we think in four or five weeks he can be back,” confirmed Mourinho.

The procedure is not complicated but it does mean that Chelsea will have only Serbian Mateja Kezman and Icelander Eidur Gudjohnsen as striking options – presuming Romanian Adrian Mutu does settle his differences with Mourinho.