Claudio Ranieri has demanded a reaction from his Leicester City side after the defending Premier League champions slumped to a 3-0 defeat against Chelsea.
Goals from Diego Costa, Eden Hazard and Victor Moses sealed a convincing victory for Antonio Conte's men at Stamford Bridge - a fourth defeat out of their previous five league fixtures for Leicester.
And Ranieri - who managed Chelsea between 2000 and 2004 - has slammed Leicester's lacklustre display, adding that he expects an immediate improvement in their upcoming Champions League clash with FC Copenhagen.
"It's clear when you come to Chelsea you know they are big team and the attention has to be at the maximum," the Italian told Sky Sports.
"We made mistakes, and we tried to react - the second half was much better - but then they scored the third goal. Now we have to react again in time for Tuesday.
"I've forgotten the first half because we were so poor. They played well but we conceded everything. The truth is our approach was not good and it was very easy for them.
"I didn't recognise my players in the first half, but I will speak to them. At least it is better that it is happening now than the end of the season.
"We now have a tough game - Copenhagen are a good team. We have to react or it will be another bad game."