Manchester United goalkeeper David De Gea believes that retired boss Sir Alex Ferguson is the best coach in history.

The 71-year-old called an end to his career at the close of last season after 26 years at Old Trafford, with David Moyes set to take over.

Ferguson brought in De Gea from Atletico Madrid back in 2011, and kept his faith in the player despite some shaky performances at the start of his career.

"He [Sir Alex] is the best coach in history," De Gea told reporters.

"I remember that the best advice he gave me is simply to give it everything. He's asked me to continue with this mentality.

"I have wanted to start a new phase in Manchester and hopefully it will go well."

Looking back on his difficult start to life in Manchester, where he came under criticism for dealing with high balls into the area, he added, "I've grown a lot.

"I think I still must grow to be among the best."