Manchester United boss Louis van Gaal is expecting more from his young defenders.
Michael Keane and Tyler Blackett were two of the defenders who performed admirably in victory over Real Madrid, even if Keane conceded the penalty which Gareth Bale converted in the first half.
Asked if the youngsters would be involved in the first team at the start of the season, van Gaal replied: "Not too early, because we have to see if they can fit in our team.
"You saw them play today and they can do the job but not for a lot of matches - they can do it for one match.
"Maybe when you give them more matches, their experience shall increase.
"But today the penalty was not so smart. He [Keane] has to learn from these errors. It's the same for Tyler - he can also play at this level but can he play match after match? That is the question and I cannot answer that at the moment."
