But the biggest cheer of the afternoon was reserved for Falcao when he came off the bench in the 67th minute.

The Colombian striker, who moved to United in a dramatic deadline-day switch from Monaco, was delighted to turn out for his new club for the first time.

“It felt good to make my debut at Old Trafford,” he said.

“It is an extraordinary stadium, a legendary stadium and I am happy to get the win. I will enjoy this moment.”

Fifteen minutes after making his grand entrance, Falcao almost scored United’s fifth.

Robert Green spilled Daley Blind’s drive and Falcao raced into the box to follow-up, but the QPR goalkeeper recovered just in time to block the former Porto man’s shot.

His failure to score was the only negative for Falcao, who was overwhelmed by the reception the home fans gave him on his debut.

“I want to say thank you to the fans. I enjoyed the welcome a lot. It was fantastic,” he said

“I almost scored. The goalkeeper was good. I hope to score the next game.”

Marcos Rojo and Blind performed strongly on their debuts while Di Maria continued to prove why he is regarded as one of the best players on the planet with another impressive display.

Falcao thinks United’s six summer signings will get even better with time.

“Bit by bit we will gel together as a team and the new players will feel more comfortable,” he said.

“I hope everything continues for us like it did on Sunday.”

Everton and Chelsea will present much tougher tests when they come to United over the course of the next month.

But the optimism that swept through Old Trafford on Sunday will take some time to dampen.

Herrera, making his return after a month-long ankle injury layoff, thinks United should be aiming as high as possible in the Premier League this year.

“I wish it can be our first step and I am sure it is,” the £29million midfielder told MUTV.

“The next games are very important because we want to be as soon as possible at the top of the league.”

QPR can only dream of such lofty ambitions.

Harry Redknapp’s team were woefully poor at Old Trafford. They gave the hosts way too much time on the ball and failed to take two clear-cut chances.

Midfielder Karl Henry admitted the game was “like a testimonial” because QPR afforded their opponents too much respect.

“It wasn’t the game plan to show them respect but when you are out there on the pitch, you see they are a good side,” Henry said.

“Their movement is very good and I think we got caught between trying to hold our shape and pressing them.

“When we did go pressing them, we didn’t go in numbers. We didn’t do what we set out to do.

“The end result is us looking like we stood off them and they are playing around like it is a testimonial.

“That’s not what we want and the manager has told us that. We will learn from this and move on.”