Everything in the end came down to the moment 20 minutes into the second half when Evan Ferguson received Billy Gilmour’s pass 30 yards from goal, turned and, with a sense of unflustered inevitability, caressed his shot into the bottom corner. It was a goal of stunning quality, his brilliant finish the centrepiece of the first of what will surely be many Premier League hat-tricks. But there was another element to the goal, which was how much space he was in.

There was an element of fortune in the buildup, Newcastle drawn forward as it appeared Gilmour had miscontrolled. But that space at the back of their midfield was an issue throughout. Although Newcastle were effective in disrupting Brighton’s preferred route out from defence, from centre-back to Gilmour, once the home side were able to advance, João Pedro often had space.

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Bruno Guimarães, fine ball-player that he is, is not a natural destroyer and, while Joelinton and Joe Willock or Sean Longstaff were able to fulfil that function last season, the introduction of Sandro Tonali, for all his attacking qualities, may have disrupted the balance. The withdrawal of Tonali and Joelinton for Longstaff and Elliot Anderson just before the hour seemed an admission of that from Eddie Howe. “The midfield is in its infancy,” the manager said. “That’s not necessarily a criticism of any one of them. It takes time to build the relationships.” Willock has suffered a setback in his attempts to return from an achilles injury and will not, as had been hoped, resume training next week.

Howe’s side have now lost three in a row and, in all three, there has perhaps been a lack of conviction. In themselves, defeats to Manchester City, Liverpool and Brighton shouldn’t be too much of a concern, but as a cluster, particularly given the nature of the defeat to Liverpool, there is perhaps a slight sense of unease. Certainly the home game against Brentford with which Newcastle resume after the international break takes on an unexpected significance.

Howe seemed determined to downplay any nascent sense of crisis, acknowledging the “ruthless” nature of the Premier League but stressing he would “analyse the game and see what we can do better” – just as he does after every match. He also pointed to “a tough fixture list” as a reason behind the run of poor form. And that is probably fair enough; Newcastle missed early chances and then, as Howe said, contributed to their own downfall. The first goal stemmed from a poor clearance from Nick Pope, then an ineffectual wag of the foot from Tonali before Pope spilled an admittedly well-hit shot from Gilmour. Ferguson’s third was the result of a big deflection and Callum Wilson’s strike, though well-taken, was too late to make a difference.

Nobody really doubts that Howe did a fine job last season and there should be no real pressure yet, but equally nobody has yet seen how Newcastle’s Saudi owners respond to disappointment. At the end of a week in which Newcastle’s new status was reinforced by a Champions League draw that set up games against Paris Saint-Germain, Borussia Dortmund and Milan, this was a reminder that, beyond the glamour, there is still the basic necessity to win football matches.

For Brighton, similarly, it had been a week of barely conceivable events: drawing Ajax, Marseille and AEK Athens in the Europa League, Pascal Gross winning a Germany call-up and the signings of Ansu Fati and Carlos Baleba. Ferguson, though, might be the most exciting element of all. “I was delighted today – not just for the goals but I’m really pleased for the performance,” said Roberto De Zerbi. “Especially in the first half he played very well, found the right position between the lines. He understood very well the position. He is working to complete his quality, he can become big, big, big. He can become the top scorer in Europe.”

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Only three other 18-year-olds – Michael Owen, Robbie Fowler and Chris Bart-Williams – have scored Premier League hat-tricks. While De Zerbi acknowledged it was probably just as well the transfer window had closed last night, he also made the point that the “most important thing for Brighton is not to keep hold of their most important player; it’s to find the replacement”.

That is the philosophy that has taken them to their current heights. And while Ferguson’s excellence means they can in effect write off last week’s defeat to West Ham as a blip, Newcastle have no such resort. These are heady times for both clubs, but Newcastle must just be starting to wonder whether this glitch might become a wobble.