Leicester City coach Claudio Ranieri said that the champions face a great struggle as they continued their slide down the Premier League.
"Only the little details make us down. We have to react as soon as possible," he said as they stare a relegation battle in the eyes just three points above the drop zone.
"What a year. Everything was right for the first six months and now everything is wrong. We have to fight."
Kevin Mirallas and Romelu Lukaku scored for Everton, leaving Leicester in 16th place.
"We have to work and react that is our medicine. We will try to do our best again," Ranieri said.
Riyad Mahrez was on the bench on Monday and Jamie Vardy was suspended.
“He’s not in good form now and I wanted to stimulate him,” Ranieri said of Mahrez. “I didn’t see him do well during the training sessions and he must give more for the team. I want more.”
An apparent protest over Vardy's suspension was completely missed by Ranieri, who said he failed to notice after 30,000 Vardy masks were handed out to home fans to wear at the game.
Vardy himself was wearing one and with the Football Association apparently the target of the stunt, FA chairman Greg Clarke was seen in one while attending the game.
However, Ranieri told the BBC: "I'm sorry, I didn't see when I came out. I don't know, it's not my matter. I didn't see. I'm sorry."
"It's difficult to say how much we missed Vardy. I didn't see the masks.”