Eden Hazard has told his fellow teammates not to get complacent as the title race could still go any way.
The Blues are top of the table and five points clear, but recorded a 2-0 loss against Tottenham at the White Hart Lane last week.
Hazard said they still had work to do as they prepare for a trip to Leicester City on Saturday.
“We know this league is difficult – you never know – anything can happen,” the Belgium international told talkSPORT.
“Now, we are top of the league, but the other teams are very strong and they want to close the gap and comeback quickly.
“We have to be ready for everything, we are in this position and we know what to do.”
Hazard helped Chelsea to the league title in 2014-15 before they finished 10th last season.
And with Leicester fighting for relegation after winning the title last season, the Chelsea midfielder feels for them.
“It’s difficult. Like Chelsea last season – we won the title – but the year after is always difficult because the opponent want to beat the champion,” Hazard said.
“They have to deal with it and they play Champions League so [they need] more energy, they lost one important player like N’Golo [Kante to Chelsea].
“We are in full confidence. We lost against Tottenham in the last game, but we are top of the league and we also want to stay top of the league.”