For David Moyes, this was just about as good a start as he could have dared to imagine. He will have appreciated the loud adaptation of the old Slade tune Cum on Feel the Noize from the end where Manchester United's supporters celebrated a winning start to the new era.
The photographers got their shot of him punching the air and Moyes must think anything is possible if he can keep Robin van Persie in this form.
The new United looks very much like the old one, with Van Persie carrying on, seamlessly, from where he left off last season, adding another two to his collection to go with the couple he scored in the Community Shield last weekend. Danny Welbeck was responsible for the other two, doubling the amount he managed in the league throughout all of last season, and the game finished with Moyes offering an appreciative handshake to Wayne Rooney.
His name was sung loudly after he came on as a 62nd-minute substitute and he was involved in the last two goals. Van Persie's finish, from outside the penalty area, was still rising as it arrowed into the roof of the net and it was telling that when he was substituted late on the home crowd joined in the applause.
Wilfried Bony had given Swansea a tiny flicker of hope a few minutes earlier but Welbeck quickly clipped in the fourth and Moyes can reflect on a day of immense satisfaction.
His complaints about United's opening run of fixtures – even ringing the Premier League's chief executive, Richard Scudamore, to voice his suspicions – had sounded transparently like a man getting his excuses in early. As it turned out, they have set themselves up perfectly for the run of games against Chelsea, Liverpool and Manchester City in the coming weeks.
Swansea had started well, quickly settling into that fluent, expansive passing style. Jonjo Shelvey, their new recruit from Liverpool, was prominently involved and, at £5m, looks like he could be a smart piece of business. Wayne Routledge and Nathan Dyer, flitting in from the two flanks, were bright and lively. Michu was proving to be a difficult opponent for Rio Ferdinand and Nemanja Vidic and United were grateful that a linesman's flag prevented him opening the scoring.
What followed was clinical from the away side. Van Persie's finish for the opening goal was expertly taken, adjusting his body shape as he tried to read the bounce from Ryan Giggs's deflected pass, steadying himself with his first touch, then hooking his shot past Michel Vorm.
The hosts had already shown signs of being shaky at the back. Giggs, played through by Van Persie, did not trust himself to outrun the Swansea defence and tried another pass, unsuccessfully, to Welbeck when he should have shot himself. Giggs also flashed a shot across the goal after Vorm had turned a left-foot effort from Welbeck into his path.
Van Persie was never going to be so generous and, once they had the lead, United quickly set about ensuring this was the key period of the game. Patrice Evra was aiming for Van Persie again in the build-up to the second goal. The ball skimmed off the striker's head into the path of Antonio Valencia, running in from the right. His shot, on the half-volley, went diagonally into the six-yard area and Welbeck applied the final touch.
Michael Laudrup brought on Bony for the second half, along with Pablo Hernandez, but the changes could not alter the game's pattern: lots of Swansea possession but always the sense that United could add more goals. Van Persie had turned one shot wide and Evra had seen a header cleared off the line before the third goal arrived after 72 minutes.
Rooney instigated the move, cutting in from the left, and his decoy run was superb, helping to create the space for Van Persie to cut back on to his left foot and let fly. It was a wonderful strike and Bony's late effort, guiding a measured right-foot shot into the bottom corner, will only have tempered Moyes's mood a little.