Evans has played an integral part in United's form in the Premier League this season after breaking up the partnership of Nemanja Vidic and Rio Ferdinand, and Ferguson has admitted that Evans has shown "great consistency".
Ferguson told The Sun: "Jonny has emerged as a real top defender and his form has been fantastic.
"The thing about young players, particularly defenders, when you get consistency from them you know you're on the right track with them. I think Jonny has shown great consistency in the last year.
"If you remember what I said about last year, it wasn't until Ferdinand and Evans played regularly together that we got a run going."
The Northern Ireland international has made 23 appearances for Manchester United this season.