Carlo Ancelotti's side have won just one league game out of the last six and Saturday's 1-1 home draw with Everton was another example of Chelsea failing to focus for a full 90 minutes.

Everton robbed Chelsea of the chance to go back to the top of the Barclays Premier League table with a headed equaliser from Jermaine Beckford four minutes from time.

Didier Drogba had put the Blues ahead with a 41st-minute penalty but Cech concedes the champions, who have now slipped to third, stopped playing in the second-half.

"We're in a period where everything is going against us and the small, little things make a difference," said Cech.

"Unfortunately the Everton one is painful because in the first-half we played very well.

"We controlled the game, we scored the goal, hit the crossbar, and then in the second half out of nothing, we stopped playing and they had chances, more possession and were dangerous.

"It is an unusual situation for everybody, the last five or six games are not what we are used to or would expect. But sometimes you have periods in sport, especially in football, when things go this way.

"When you are going through a difficult period you have it on your mind that you have to defend better, but sometimes it's not the way it should be.

"We need to be more relaxed and we have the experience to be, but it seems every time we got the ball in the second half we made the wrong choice. That's why in the end they got their equaliser.

"There is still a positive in there, though, as the first-half showed we still have the quality to win games, but our problem recently has been that we cannot keep the performance for 90 minutes - we have periods of play where we are not there, and it has been more or less all season, even games where we won 6-0, at Wigan the first half was poor.

"We are working on it and trying to improve things, we just need a trigger point, to get a break in a game, and I think everything will be fine. This could be the game on Wednesday against Marseille."

Chelsea face Marseille in their final Champions League Group F game at the Stade Velodrome on having already bagged top spot.

Cech will be fit to face the French side, unless he is rested, after requiring stitches in a facial wound from a late clash with the boot of Everton's Tim Cahill.

Cahill's challenge left captain John Terry fuming and the pair had to be separated as Cech lay motionless on the ground.

Cech already wears a protective helmet after fracturing his skull against Reading in 2006 but the Czech Republic goalkeeper revealed he was saved from further damage by his quick reactions.

"When I went for the ball I saw the boot coming from behind JT, so I knew there was going to be a clash," he admitted. "I turned my head away and that's what I think made less damage than it would have done.

"Afterwards I just tried not to move because as soon as it happened I could feel the blood come into my eye and I have contact lenses, so my concern was what I would do if I had to change my lens!"