Rafa Benitez says "mistake after mistake" saw Everton collapse to an embarrassing defeat at home to Watford.
Richarlison came off the bench to put the Blues 2-1 ahead just past the hour mark at Goodison today but Watford scored four times in the final stages to leave the home fans angry.
Many supporters left the ground after Watford's fourth goal and Benitez says he fully understood the reaction of fans to the heaviest home loss in nearly three years.
"Really, disappointed for sure," Benitez said.
"With Richarlison on the pitch, we scored a goal and were ahead but started making mistake after mistake, we conceded too many goals in a few minutes because we couldn't manage a situation that was in our favour with the second goal."
Benitez added: "At the end, we scored two goals and it was not easy. Richarlison came on the pitch, scored and the fans were behind the team.
"Everything was positive and then we started making mistakes. We gave them a chance to have a corner that we could do better and then we couldn't defend the corner.
"Every time they regained the ball we were in a bad position or making a mistake, giving them hope, more belief on the counter-attack."
Benitez said the fans' anger was justified but he hopes the players can retain the level of support they have received so far this season, saying how important the backing of the faithful is.
"I am really disappointed because we have a very good connection with the fans" he said.
"From the beginning they were really good, supporting the team and behind every player. We have now made some mistakes and you can understand the frustration of the fans but we have to be sure we change these things and keep the fans on board because they are really important for us."
Benitez concluded: "We have to show character and personality to manage any situation or mistake and we didn't do it. We kept making mistakes."
