The Briton, who entered the Stella Artois championships on a wildcard, said: "It's going to be difficult to do what he's done, but I've got to aim for the top.
"One thing you have to look at is that Nadal, for someone who's 19, is physically better than everybody else in the world.
"I've maybe got two or three years because my body has not developed like his. I've still got some growing to do. I've got to fill out and get stronger."
Occasionally prone to on-court theatrics, Murray has been based in Barcelona at the Sanchez-Casal academy for three years after hearing about it from Nadal at a junior tournament.
Like the Spaniard, his game is best-suited to clay, and the grass court competitions provide a steep learning curve.
Murray admits he feels uncomfortable trying to serve and volley at Queen's, despite his efforts on the practice courts. His decision to hone his game in Spain may not help in that respect but it was partly designed to take him away from British pressure.
Now he is back in the United Kingdom, he wants to make the most of his support. He said: "I am ready for the attention. I'm looking forward to it.
"I played in some big matches before but the crowd has never really been with me. I played in the Davis Cup in Israel and there was a really big crowd there but pretty much 5,000 of them were against me.
"I also played in the junior US Open final, which was a big match, and the crowd was kind of half and half. But now to play at home in front of a lot of people is good motivation.
"It really helps. You feel like you've got a lot of people there helping you and are wanting you to win. It really makes you play better."
