Chelsea boss Jose Mourinho says his side's poor form is because he is trying to improve their style of play.
The club have lost their last two games - against and - and made their worst league start in 10 years.
"I don't like the way Chelsea were playing in the last couple of years. The club doesn't like it and we want to change," Mourinho said.
"When you want to build something different and the players are adapted and comfortable - it's more difficult."
The Portuguese says that he cannot predict how long it will take for his tactical changes to improve results.
"Tomorrow maybe we win 3-0 against Fulham and everything is perfect, or maybe I will lose for the first time at home at Chelsea in four years and 200 league matches, and it is a big story.
"Football is not mathematic. I don't know."
Since Mourinho's first stint at Chelsea ended abruptly in September 2007, Avram Grant, Felipe Scolari, Guus Hiddink, Carlo Ancelotti, Andre Villas-Boas, Roberto Di Matteo and Rafael Benitez have all occupied the manager's role at Stamford Bridge.
Mourinho, who said that he would not play with "low blocks" - a reference to deep-lying defence - or with centre-backs deployed in midfield, claimed he would not be happy with victories alone.
"If someone expects me to play against Fulham tomorrow with nine players behind the ball and wait for them to make a mistake and win 1-0, then I will not go home happy," he added.
"We have a lot to do. The work I have to do does not sell papers - big defeats and big victories do - but the only thing I can do is to have belief in my players and wait for the results to come."
Chelsea's haul of seven points from their opening four Premier League games is their worst start to a campaign since Russian billionaire Roman Abramovich bought the club in the summer of 2003.
Mourinho insists however, that his revamp of their tactics cannot be deemed a failure until they fall out of contention for silverware, as they did last season.
"We have lost nothing. You like to compare things but we didn't finish third in the Champions League, we did not get relegated to the Europa League and we did not finish third in the Premier League," he said.