Chelsea boss Mauricio Pochettino has challenged his young team to find a ruthless streak ahead of Monday night's clash with Everton.
Pochettino admits an improvement in mentality is needed to end their inconsistency.
"We have enough talent to win games," he said. "But the difficult thing in the Premier League is another phase, when you don't have the ball.
"When you don't have the ball, you need to have the balls. Understand? To have the b***s to recover the ball."
Pochettino continued: "I think it's about training and trying to show the way we need to compete and then they need to deliver on the pitch.
"It's a process to be very competitive, very tough. I think the way we drew the game against Sheffield United, we need to all to feel very disappointed because did you see the McBurnie goal?
"We lose one challenge. We lose the second, the third and the fourth and the fifth. And then we concede in the same action. And that was the last minute of the game.
"It's about having the capacity to go there and to say, 'We are a winner, I'm going to win this challenge, I'm going to be strong, I'm going to defend, I'm going to not concede a goal'.
"That is nothing more than mentality and all being together."
