Manchester United boss Sir Alex Ferguson admits their current FA Youth Cup team is very raw.

The Under-18s progressed to the fifth round of the famous competition with a 2-1 victory against Derby County at Altrincham's Moss Lane on Wednesday night in front of the United manager, who sat alongside chief executive David Gill in the stands.

It is felt that the talented teenagers have a lot of growing and maturing still to do so everybody at the club is delighted that another run in the tournament is unfolding.

"It's a very young group," Sir Alex told MUTV before the win against the Rams. "Physically, they are well short of last year's group and age-wise too.

"I think we've only got one or two players performing from last year. I think Tyler Blackett is one player left from last year [Gyliano van Velzen is another]. It's a young squad with a lot of 16-year-olds in the team.

"You hope if they get through this stage, by the turn of the next two or three months, they start to develop physically and it may give them a little chance in that respect."