Adam Bate finds out by speaking to the man who has followed Longstaff since he was a boy, the international striker who spotted something special, and the manager who gave him his debut in English football…
Not many Premier League players can be found watching their old youth team train but Sean Longstaff is one of them. "You will just see him of a night time leaning on the barrier watching the kids train," says John Farrage, chairman of North Shields Juniors. "He has a nephew at the club so he often just stands out of the way watching the sessions.
"Until someone spots him that is."
It is an increasingly regular occurrence for the 21-year-old Newcastle midfielder. At the start of the year, he had not even made his Premier League debut. By the first week of March, his season was over because of injury. But such was his impact in the intervening period that there is now talk of a move to Manchester United this summer. It is a remarkable rise.
Longstaff outran every other player on the pitch in his first five starts and Newcastle have won every game that he has played at St James' Park. He scored in the last of them and was a key figure in the win over Manchester City too. Pep Guardiola admitted that his team "could not deal with" the Newcastle holding midfielders that day. It was some compliment.
Still, there is a perception that this is all too much too soon. That United's interest says more about their desperation than what Longstaff has done so far. But speak to those who have worked with him and there is a different sentiment. They talk of a young player who is not like the rest. Someone who possesses qualities that other midfielders do not.
It was Kilmarnock where Longstaff made his professional debut as a teenager. Sent up to Scotland to prove his worth, he promptly scored a last-minute winner on his first appearance in the Scottish Premiership. Kris Boyd was the man who opened the scoring that afternoon and the former Scotland international could not have been more impressed.
"A lot of people look down on the Scottish game but for a young kid coming out of the academy it can make or break you," Boyd tells Sky Sports. "It is the first step into the big bad world of football. No arm around the shoulder. If you don't buy into that it can be difficult to adapt and a lot of the youngsters who come up from England end up getting sent back.
"Sean Longstaff was totally different."
Boyd remembers him being "magnificent" and taking to it "like a duck to water" in terms of how he adjusted to first-team football. Longstaff finished with three goals from his 17 appearances but it was his decision-making in midfield that stood out as unusual. Boyd saw someone prepared to do the things that other academy players of his age would not.
He is just different from the modern-day footballer. Sean Longstaff is a throwback.
"He is just different from the modern-day footballer," he explains. "A lot of youngsters who are coming through the academies these days, they just want to keep it simple and retain the ball for their team. We are all caught up in this statistical world that records how many passes you have made and how many times you have given it away.
"Sean Longstaff is a throwback. He is willing to take risks. He is a midfielder who is willing to take a shot, willing to try that forward pass. He might lose it five times out of six but he is prepared to do that because he knows that the sixth time it might lead to the goal that wins the game. He is always on the front foot and that's what I like about him.
"As a forward, if you are making runs and the ball is not coming to you, you get frustrated and go in search of it in different areas. But you could make runs off Sean Longstaff because you knew he would take the risks to find you. You could go because he would see it. He had great vision. He would play the eye-of-the-needle pass to get his striker in on goal.
"Maybe that's the reason why these clubs are now looking at him. Football goes in cycles so maybe the game has changed again and they don't just want robots who can get the ball and play safe possession. They want something different. They want midfielders who can create and score goals. Sean Longstaff definitely falls into that category."
While it was his passing that set him apart for Boyd, it was at Blackpool that Longstaff's shooting ability really became apparent. He scored in his first four league games in English football, going on to find the net nine times during that season in League One. Gary Bowyer was the Blackpool manager at the time and he is another who saw something special.
"We watched his games for Kilmarnock and we went for it," Bowyer tells Sky Sports. "He had a fabulous season. The return of goals from midfield was outstanding. He had this unbelievable knack for shooting and being successful at it so we encouraged it. He can score from long range and most of his goals for us came from distance. He did brilliantly."
As well as the goals, it was the attitude that struck a chord with Bowyer. The son of an international ice hockey player, Longstaff's determination to improve is ingrained. "After each game we would sit down on a Monday or a Tuesday and go through his individual clips, looking at what he did well and things he could improve on," recalls Bowyer.
"That's the good thing about him, he's very level-headed. His dad has come from a sporting background so there is no way Sean will be allowed to get carried away with himself. But that inner drive to get better is there. He is always looking to improve. Speak to him one-on-one and his knowledge of the game is good. That's fantastic for someone of his age."
It is the reason why there is such optimism about Longstaff's long-term prospects. All young players are tested and the challenge is to come through that. Every test that Longstaff has had in his short career, he has passed. Given his mentality, there is every reason to believe that he will continue to find the solutions even as those tests become more difficult.
"Just look at his career so far," says Boyd. "At Kilmarnock, he settled straight away. He was really successful at Blackpool and he hasn't looked out of place at Newcastle either. In fact, you could say they missed him when he wasn't there. He has progressed through all of the levels and he keeps getting better.
"Did I think he could be signing for Manchester United in just a couple of years? No. But it just shows what hard work and determination can do. It would not surprise me at all if he went there and did really well. He has the talent and he has the work ethic."
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That's the player they recognise at North Shields too. Here's another story. The club recently had a presentation night for their junior teams and were keen for Longstaff to be on hand to give out the awards. The event took place over two nights - Friday and Saturday - from 6pm to 11pm. Longstaff was on stage for much of it. He wanted to be there.
"It made the kids' night," Farrage tells Sky Sports. "It was fantastic and he did the two full nights. You couldn't ask for anything more."
But could they ask him to stay at Newcastle amid interest from Manchester United? Farrage is still in touch - "I text him after every game just to tell him where he is going wrong," he jokes - but there will be no pressure from those who first set eyes on him as a four-year-old boy.
"I have followed his progress all the way and we will follow him whatever happens," he adds. "I haven't asked him about it because it wouldn't be right. He has probably got a million things on his mind and he has got good people around him. I do hope he stays though because the way Newcastle are going he would be a superstar up here."
Perhaps Sean Longstaff could be a superstar anywhere.
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