The Ivory Coast international was carried off in the 83rd minute of Chelsea's 3-0 Barclays Premier League victory over Tottenham today.

Drogba had already made and scored one of Chelsea's goals before he had to be substituted.

The victory earned Chelsea a new club record of 11 straight wins, better than the one forged by Jose Mourinho, but Ancelotti was more concerned with the condition of his top striker.

Drogba has now scored five goals and was unplayable against Spurs and while the Italian is hoping the injury is nothing more than cramp, he believes they have enough in reserve to cope without him.

"We don't know precisely what happened," said Ancelotti. "It is too early. We will have to wait a few days. We hope it is only cramp.

"We hope tomorrow we will have a precise diagnosis of the situation. It is a calf injury but he felt that he had cramp. If it is cramp, it is good for us.

"We have played without Didier before. He is a very important player for us, a fantastic player. I think we can play well without Didier.

"In the last game against Porto we won without Didier and we have Nicolas Anelka, Salomon Kalou, we have Daniel Sturridge and Fabio Borini.

"Borini is a young player and we are pleased he came on for his first game in the Premier League. We have a very good academy and we want to take a young player into the first team.

"All the players did a very good job. The match was easy in the second half. If you don't do a good job on the pitch against Tottenham you cannot win 3-0.

"We need to maintain the mental attitude and win our next game against QPR in the Carling Cup on Wednesday.

"Our next game will not be easy. We do not think about records, only wining the next game."

Ancelotti would not be drawn on Robbie Keane's penalty appeal which was rejected by referee Howard Webb.

Keane went down under a challenge by Ricardo Carvalho but Webb was not convinced and waved play on.

"I don't know if Tottenham should have had a penalty, I am not a referee," said the Italian.

"I do not like to speak about the job of the referee. I prefer to speak about the match. The referee did a good job because there was a lot of respect.

"There was no problem with his refereeing. I am very happy because we won a difficult game.

"Tottenham are very good opponents and they played very good in the first half.

"The second half was better for us. We won the ball in our midfield and did a very good counter-attack for the second goal.

"It was very important to win this game. It was a derby and we played well against a very good team."

Ancelotti watched Manchester United's 4-3 win over rivals City before Chelsea's game but remains focused purely on his own team.

"I saw Manchester United's game," he added. "It was a fantastic game, unbelievable, but in England there are matches of this kind.

"The fans of Manchester United are very happy, the fans of City not so happy.

"When one team score in the last minute it means it is a very good team.

"But I am only interested in Chelsea playing well and winning."