Chelsea's Brazilian defender Alex has revealed how his father inspired him 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 now 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," said Alex.

"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 erupted 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 for me 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."

Didier Drogba has withdrawn from the Ivory Coast's final World Cup qualifier against Guinea on Saturday, although Chelsea have yet to confirm his absence.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 Chelsea striker remained in London for treatment after sustaining a chest injury against Manchester United.

The 31-year-old was kicked in the chest by defender Jonny Evans in Sunday's 1-0 Barclays Premier League victory at Stamford Bridge.

Drogba may be fit enough to play in his country's friendly international against Germany in Gelsenkirchen next Wednesday.

Olympique Marseille striker Bakary Kone is also out of this weekend's match in Abidjan.

The Ivorians have already qualified for next year's World Cup finals in South Africa.