The 22-year-old Brazilian is the only right-sided full-back available to United at present, as Phil Jones and Chris Smalling are out injured and twin brother Fabio is on loan at Queens Park Rangers.

Rafael, who was voted the club’s Player of the Month and won Goal of the Month for September, has staked his claim for a permanent first-team place with a level of consistency which had been lacking in previous seasons.

Ferguson said: “He is maturing and learning all the time. Rafael has all the ingredients of a great player. He is blessed with great enthusiasm, skill and speed. He was quite impulsive and tended to over-commit himself.

“We have gone over it a few times but, bit by bit, it is all coming together and he was easily our best player Saturday.”

Rafael continued his good form against Stoke City on Saturday, which the Red Devils won 4-2, making important interventions and withstanding the intense physical challenge presented by the Potters.

Sir Alex believes the young defender is starting to mature into a key player for the club, following four years at Old Trafford, and Rafael would agree.

The right-back said: “The way I play for United has changed a little bit and I have scored some goals as well.

“But mature is the word. I always want the ball. Now I read the game more and know what the opposing player is going to do.”