Didier Drogba may be forced to miss another Champions League game Chelsea but this time it is caused by injury.

The Ivory Coast international has been unavailable for the Blues because of a suspension he received in last year's semi-final but after the win over Bolton on the weekend, he pulled up with a slight leg problem that could keep him out of the fourth group stage match.

"Drogba had a little problem with his leg and we have to wait," said Chelsea boss Carlo Ancelotti. "If he is well, he can play.

"I would like to change something and we have fresh players in good condition. I want to use all the players because we have a lot of matches and we have to play well every game. I think it would be good for us to change something against Atletico Madrid."

Chelsea midfielder Frank Lampard said the loss of Drogba is a big one but admitted the side was travelling well enough regardless who was out on the park.

"Didier is obviously a top-class player and in great form as well," said the midfield star. "Everybody would want him back and involved, but I think we've done very well without him.

"It's just a big bonus he's back and hopefully he can step straight in and carry on with his league form because he's scoring in every game at the moment.

"It will be a very difficult game, but we understand if we win against Atletico, we are through. We know how tough it will be and they are a very good attacking team. They have the quality to make it difficult for us."