The Blues have slipped to fifth in the table, six points behind leaders Manchester United having played a game more, after just two wins in their last 10 Premier League games.
Striker Drogba said: 'Chelsea's current position compared to last season is actually very similar but maybe our injuries and less goals have brought about a negative mood.
Not enough: Drogba thought he had won it for Chelsea against Aston Villa but they were pegged back to 3-3
'In the last weeks (manager) Carlo Ancelotti has been unhappy - and the squad, too. Chelsea are not accustomed to defeats and the dressing room has suffered. But the season is long and it is normal to suffer lots of changes.
'We play Wolves next and I hope our bad phase has disappeared. We need three points and that's the most important thing.'
Drogba has been fighting his own personal battles this season and his fitness problems have been well documented, not least the bout of malaria which was diagnosed in November.
The 32-year-old has managed eight top-flight goals since the start of the campaign. Drogba scored 29 last season and admitted he is some way short of that form.
He added in The Sun: 'Injuries and the malaria have damaged my performances. I am still not 100 per cent but I am fighting in each match to improve my playing levels and help the team.
'This season has been complicated for me by physical problems. It has not been easy to regain my strength but we need the points and my presence is necessary. I have always sacrificed for the team - and Chelsea need me.'
Testing times: Drogba (second left) and his team-mates cannot get the better of Villa at Stamford Bridge
Chelsea have been criticised for not finding replacements for the likes of Michael Ballack, Ricardo Carvalho, Deco, Joe Cole and Juliano Belletti.
Russian owner Roman Abramovich also angered sections for the support by sacking Ray Wilkins as Ancelotti's assistant.
Wilkins' departure coincided with the start of the slump but Drogba said: 'Ray's exit was a decision of the club and footballers are obliged to accept it. And although many people believe our situation is difficult Chelsea still have a chance to win the title.
'The league is very open and anything is possible. This season many players like Spurs' Gareth Bale, Marouane Chamakh at Arsenal, Manchester United's Nani and Yaya Toure for Manchester City have all progressed and they are helping their teams make big challenges.
'So emotions will run high until the end of the season - but we cannot afford any more errors. And we need to be invincible at Stamford Bridge.
Pleasantly surprised: Vidic (right) has led Manchester United to the top of the pile as Chelsea have slipped up
'Reinforcements in January? It's always complicated. More players don't necessarily guarantee victories. For us now each match is a final - and we need wins.'
Manchester United captain Nemanja Vidic is shocked at how things have changed for Chelsea.
He said: 'This season is very strange. If you had told me five weeks ago that Chelsea would be in the position they are now, I wouldn't have believed it.
'Everyone thought they were the strongest team and that they would win the title. But then they didn't win for six games.
'And look how many points we have lost this season. If someone had told me this would happen, I would have said we could not win the league. But here we are top and still unbeaten.'
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