Remi Garde says his defenders must show more "desire" if Aston Villa are to have any chance of avoiding relegation.
The Villa boss made big changes against Everton on Tuesday night, recalling Brad Guzan in goal and Micah Richards and Ciaran Clark to play alongside Joleon Lescott in a central defensive trio as part of a 3-5-3 formation.
The result was another defeat, Villa losing 3-1.
Garde's plans went out the window after only five minutes when Ramiro Funes Mori lost Richards and powered home a header unmarked from a corner.
Goals from Aaron Lennon and Romelu Lukaku extended Everton's lead before substitute Rudy Gestede headed a late consolation for Villa, who remain eight points adrift of safety.
"I thought the shape would fit better to give them problems, but we couldn't have made a worse start," said Garde.
"Unfortunately we conceded a goal from a set-piece very early. Then the plan is difficult to hold. We had to change a little bit. But conceding the second goal close to the first one also wasn't the best situation we wanted, of course.
"In football, 30 per cent of goals are scored in set-pieces. This is part of the game. I don't want to blame any one player. We all have to do better.
"We conceded an early goal against [Manchester] City in the cup, one against Liverpool was at a set-piece and another one here [against Everton].
"Sometimes I think the way you defend at set-pieces and the commitment you put at set-pieces is very important. It's not a question of tactics, it's the desire to clear the ball."