Maurizio Sarri stood by his decision to deploy Eden Hazard as a centre-forward following Chelsea’s shock defeat at home to Leicester.
Hazard was again asked to operate as a so-called false nine in the game at Stamford Bridge, where Jamie Vardy scored a second-half winner for the Foxes.
Blues boss Sarri opted not to start with striker Olivier Giroud, who was brought on after an hour.
But Sarri said: “I was really very happy at the end of the first half, because for me we played very well.
“We were dangerous. We conceded nothing to the opponents in the first half. I was very happy with the team and the solution of Hazard as a striker.
“Then, after the goal, the position of Hazard was not important.”
Hazard hit the bar before the interval and Chelsea seemed certain to step up a gear in the second half.
Instead, they ran out of ideas and looked totally disjointed after Vardy’s goal.
“I think we played very well for 55 minutes, we played very good football, and after the goal the reaction was for me a strange reaction,” Sarri said.
“It was not as a team but as 11 different players and so it was really very strange. We could have done better.
“We had only to continue to play as in the first part of the match. There was time to score without a reaction like a team shocked and in mental confusion.”
Sarri has criticised his players a number of times this season for fading in matches after a bright start.
Asked what was causing the reoccurring problem, he said: “I don’t know. If I knew I would have solved the problem before this match.
“It’s difficult to understand because we have players with long experience.”