Petrucci continues to impress, scoring a superb set-piece winner against Leicester City in the last fixture.
"I try to practice free-kicks and everything else if it's possible," the 22-year-old told ManUtd.com. "I need to try to do it more often. If I want to score, I need to try to shoot from distance as well. It gives you a good feeling - especially if you score a nice goal. A goal is always a goal but, if you score a nice one, it is even better."