Andre Villas-Boas blamed missed chances and a lack of confidence for his side's third defeat at home this season, a 1-3 loss to Aston Villa.
"We had enough chances, good ones. We were punished heavily when they had their chances.
"We need to find initiatives from somewhere," he conceded.
"It was a disappointing result as top teams also dropped points."
Villas-Boas added: "It's difficult to put in perspective the title."
He added that it was "fantasy to think they could win the title - our ambition is now to finish at least fourth which is unacceptable.
"The minimum requirement for a club like Chelsea is first place,"
A close-range strike from Stephen Ireland on 28th minutes cancelled out Didier Drogba's 150th Chelsea goal from the spot six minutes earlier. Further efforts from Stiliyan Petrov and sub Darren Bent in the final seven minutes consigned Chelsea to their third home defeat of the season.
The home players and manger left the pitch with boos ringing in the ears from frustrated supporters.
"We want to repay the fans' trust in us," he said. "The booing is acceptable. They have every right to be disappointed.
"The away support is fantastic and the home support is improving. We won't run away from our responsibilities."
Drogba's spot-kick strike equaled the totals achieved by Chelsea legends Peter Osgood and Roy Bentley.
Villas-Boas said of Drogba "Didier's goal was an emotional one. It might be his last game. I hope he is available for the FA Cup tie against Portsmouth next week."
Drogba could be called up by his national side on January 7th in preparation for the African Cup of Nations later in the month.
Villas-Boas then added that he did not think it would be Drogba's last game for Chelsea per se but did not rule out a move away from the Stamford Bridge outfit.
Chelsea face Wolverhampton Wanderers at Molineux on Monday and Villas-Boas wanted to put a positive spin on events.
"We are below the top four, but it could all change within 24 hours," he said.