There has been £150m spent on improving the squad this summer, after the Red Devils failed to win any of their first four games, and the arrivals of the likes of Radamel Falcao and Angel di Maria have given Rooney cause for optimism.
"Obviously last season, we all know we were not good enough," he told The Mirror. "But the time is now right to get these top players to get us back to where we belong – winning titles again.
"These are exciting, interesting times for United. We have not got off to the best of starts, but we are very confident things will improve quickly.
"Falcao is a world-class player and I am looking forward to getting back and working with him. It's a great signing but it's also a great statement of intent from the club."
Falcao and Di Maria could both feature at Old Trafford for the first time in a Man Utd shirt when they take on Queens Park Rangers at home this afternoon, and you can follow the game live on Sports Mole from 3pm.