The Blues have now lost five of their last eight Premier League matches and fell further behind in the race for Champions League qualification
Chelsea boss Frank Lampard has revealed his concerns over his side's poor form after going down 2-0 to Leicester City on Tuesday .
Wilfred Ndidi and James Maddison both struck in the first half to consign the Blues to defeat at the King Power Stadium.
The result leaves Chelsea in eighth place, five points away from Liverpool in the final Champions League qualification spot having played a game more than Jurgen Klopp's defending champions.
Tuesday's reverse was the team's fifth in their last eight Premier League outings, a torrid run of form that has heightened the pressure on their manager.
And Lampard acknowledged that his charges cannot ignore the reality of the situation.
"We won against Fulham without playing brilliant, from that we come and lose a game so it's a small step backwards," the manager explained to Sky Sports after the final whistle.
"I am worried about the slump - from the form we were in to get so quickly into the form we're now in and we've had some wins, but five losses in eight isn't where we want to be.
"It takes character to get out of that - I'm not against the lads in the dressing room because they're disappointed. It's a young team and it's a big lesson that if you come off it and think you're fine then you've got to get yourself out of the hole."
Despite his disappointment, Lampard was generous in his praise for the victorious hosts, whom he admitted outplayed Chelsea across the 90 minutes.
"Beaten by the better team. They were sharper than us, ran more than us and they looked in form - we looked out of form. Disappointing goal form a set piece and the second goal is just not good enough," he added.
"There were quite a lot of moments where our sharpness wasn't there, those are moments you have to dig in and the basics are important like running and sprinting and we didn't do that.
"The most disappointing thing is to come here and lose the game but the basics off the ball are important.
"The game on the ball was a bit slow at times but it was okay, we created a few opportunities and I thought it was a penalty (a first-half foul on Christian Pulisic just outside the box) but I'm not going to lean on those things. We weren't good enough."
Chelsea now turn their attention to the FA Cup, hosting Luton Town in the fifth round on Sunday.