Chelsea defender Jose Bosingwa will be out for around three months after undergoing surgery on his left knee.

The 27-year-old has been out since mid-October with the problem and will now not return until the new year.

A statement released on www.chelseafc.com read: "Chelsea Football Club can confirm that Jose Bosingwa underwent arthroscopic surgery on his left knee this week. His recovery time will be approximately three months."

The Blues, who lead the Barclays Premier League by five points from Arsenal and Manchester United, were, however, buoyed by the news that England left-back Ashley Cole does not need to go under the knife following a shin injury.

"Meanwhile, Ashley Cole is suffering from an aggravation of a depressed fracture of the tibia, originally picked up against Atletico Madrid at Stamford Bridge," the statement added.

"The injury will not require surgery."

Portugal international Bosingwa has made eight appearances for Chelsea this term, the most recent of which came when he was taken off in the second half of the 2-1 loss to Aston Villa on October 17.

Manager Carlo Ancelotti was adamant he was happy with the squad following the Court of Arbitration for Sport's suspension of the FIFA transfer ban imposed over the club's recruitment of Gael Kakuta from French club Lens.

But with Didier Drogba, Salomon Kalou, Michael Essien and John Obi Mikel all set to miss most of January because of their participation in the African Nations Cup and the latest blow with Bosingwa, the Italian may be forced into a re-think.

The news about Cole is brighter, although a time scale for the left-back's return is yet to be made public.

The 28-year-old withdrew from the England squad for Saturday's friendly with Brazil in Qatar after playing a full part in the Blues' 1-0 defeat of Manchester United at Stamford Bridge last Sunday.

The left-back had missed three games after initially sustaining the injury in the 4-0 home win against Atletico Madrid in the Champions League last month.

He returned against Madrid in the return Group D game last week but required a pain-killing injection in order to play against United.

Drogba has withdrawn from the Ivory Coast's final World Cup qualifier against Guinea on Saturday, although Chelsea have yet to confirm his absence.

The striker remained in London for treatment after sustaining a chest injury against United.

The 31-year-old was kicked in the chest by defender Jonny Evans in the win at Stamford Bridge.

Drogba may be fit enough to play in next Wednesday's friendly international against Germany in Gelsenkirchen for the World Cup-bound Ivorians.

Chelsea's Alex is not among those who will line up for Brazil against England in Doha.

The 27-year-old former PSV Eindhoven defender today revealed how his father helped him decide to sign a new four-year contract with the club.

Alex looked set to quit Stamford Bridge last summer but remained with the Blues and put pen to paper on a new contract last month.

The centre-half had spent much of his time since the summer recovering from groin surgery, but Chelsea were keen to offer him a new contract in the light of the club's transfer ban by FIFA.

Alex has regained full fitness and made starts against Bolton at home and away at Atletico Madrid in the Champions League. He was also a late substitute in the 1-0 win over Manchester United last Sunday.

"I am very happy to stay here, because I really like playing for Chelsea," he said.

"I spoke with my father first and he said, 'It is a good club, you have to stay here more years' - and of course I am happy here, so I signed the contract.

"My father is very important to me. I always speak with him when I have a decision. On my first day at Chelsea he came with me and he stayed one month in London while I was living in the hotel. He came to training every day.

"I believe I can do more for Chelsea - I have played only two games since my operation but I want to do more, so I keep training hard."

Alex now wants to get as much football under his belt in order to be part of the Brazil squad that takes part in the World Cup finals in South Africa next summer.

But his season was disrupted by a nagging groin problem, which first troubled him on the club's pre-season tour of America.

"I started the pre-season tour in America but I was training and playing with pain always, so I had to ask the doctor if I could go for the operation. Now it is okay. I can do everything without pain - train, run and shoot.

"I had to make a decision to be out for three or four months so that I could do everything without pain, or play on as I was before.

"Now I have to continue my improvement and train very well. I'm very happy to be playing again."