Manchester United youth chief Warren Joyce admits his players must be mentally tougher.
United were bundled out of the Lancashire Senior Cup quarterfinals this week by Bolton Wanderers.
"I've said to them that really, in 90 minutes, regardless of whatever frustrations we might have about the development and fact we didn't do well enough, we've still got a five-game unbeaten run," Joyce told MUTV. "We have to be a lot better on Friday than we were on Monday to get the right result.
"Obviously, I'm disappointed to go out because it's a competition we've won several times in the last few years but I'm more disappointed with the performance. We've had a good run of form and played slick football with a lot of energy about our play as well, but I didn't think that was there.
"Sometimes, you can have gut feelings before the game and, when I looked at them in the warm-up, I just thought one or two were not quite mentally as sharp as they should be and that showed in their play.
"This group obviously had disappointment in the UEFA Youth League and we've put some demands on them in the last few weeks. They responded really well but, at times when it's not going great for you, you have got to see games out. To concede in the way we did was really disappointing as it was just basic things."
