Manchester City boss Mark Hughes says the challenge of building a new team keeps Manchester United manager Sir Alex Ferguson young.

"Sir Alex Ferguson has always had the ambition and drive to succeed," Hughes said. "He has a good team around him but the desire and hunger comes from within.

"He gets excited when he builds teams. It keeps him young and that thrill of winning trophies has always been with him."

Ferguson has also never been scared to embrace new technology, as shown by Ben Foster's use of an iPod prior to Sunday's Carling Cup shoot-out win over Tottenham Hotspur.

"The key to his longevity is that he is able to move with the times and embrace new ideas," Hughes said. "A lot of managers have fallen by the wayside because they do not have that ability. But it is one of his strengths."