The 20-year-old was a late arrival on tour after a successful European Under-21 Championship campaign in Spain.
"David de Gea will start on Saturday," said Ferguson.
"He has had a few days' training now and has done fine. Being young and coming into the English game, the one area we are not sure about is that he may need time.
"David has similar qualities. He has terrific composure for a young man. He is quick. His use of the ball is excellent. There are good ingredients there. Hopefully that shows itself as we get into the season."