Deco feels it's unfair of United fans to expect Nani to replace the now Real Madrid star.
He told chelseafc.com: "I think it is different. There is a pressure on Nani to replace Ronaldo which is difficult, but he has the quality,' debated the former Barça man. He is young and I think he can do well at Man U. Of course it is difficult to compare him with Ronaldo, this is not the best way. It is important for him to play and he is playing well.
"Any team wants to have the best players. Of course when a team loses an important player, one of the best in the world, it is difficult for them. Ronaldo is a fantastic player, but they still have a good squad with good players. And it isn't just Ronaldo, they lost Tevez who was also an important player."