The 22-year-old Portuguese winger currently boasts the most assists of all midfielders in the top flight this term and is steadily blossoming into a capable successor for Cristiano Ronaldo.
And Ferguson believes Nani has adapted to the rigours of the Premier League more speedily than his Portugal team-mate.
“Ronaldo was exceptional,” said Ferguson. “He is a one-in-a-lifetime player. But it did take him time to settle and develop in the English game. If anything, Nani has done it a bit quicker.
The United manager added: “I don’t need to trumpet his improvement. He has been consistent all season.
“He is a match-winner who creates goals and he scores them. He had seven strikes against City and that is a high ratio for a winger, particularly in a big game.
“He is showing maturity now. Every time he gets near the box you think something is going to happen. When you get that, you have a great player.”
Nani joined United from Sporting Lisbon for around Ã¢â€šÂ¬25.5m in 2007 and has made 136 appearances, scoring 27 goals.
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