Aitor Karanka has accepted that he made mistakes before Middlesbrough's 2-0 defeat to Wolverhampton Wanderers on Tuesday evening.
Despite refusing to reveal which players should have been left out, Karanka has insisted that he will make up for the errors ahead of Saturday's game against Watford.
"The person who made the first mistake was me. I didn't choose the right players to play," the Spaniard told the Northern Echo.
"I am the first person who made a mistake and after that, we didn't play the way we are used to playing, we didn't play with the intensity we have been. We did not have that intensity which we normally see from my players.
"I know what mistakes I made, but I am not going to say. I need to learn every single game and we have another on Saturday."
Middlesbrough were unbeaten in seven Championship games before the loss to Wolves.