United's teenage sensation Rashford has been in wonderful form during the current campaign as well and he has already managed to find the back of the net on six occasions this season, including a hat-trick on debut for the England U21 side.
Given his brilliant run in front of goal, Rashford looks set to play a key role for United this term and club captain Rooney believes that the 18-year-old has enjoyed so much success at Old Trafford due to the fact that he has been handed the freedom to play on instinct.
Rooney told MUTV: "You want them to play and express themselves – what you're seeing is Marcus expressing himself and scoring goals, which is great for the team.
"He's a bit quicker than I was! I think, as a young lad going in, you almost feel like there's nothing to lose and no pressure.
"If you're allowed to have moments where it doesn't go for you, then you can have those moments everyone looks back on.
"You're just playing football on instinct and that's the best way to play it."