Arthur Melo turned one way, turned the other way and turned into Xavi Hernandez. At Wembley of all places, a kind of spiritual home for their history and identity, stage of moments that defined them, culés saw Barcelona be Barcelona; Sergio Busquets be Sergio Busquets, not misplacing a single pass -- literally, not figuratively -- and Lionel Messi be Lionel Messi, only more so somehow, a 90-minute highlight reel, sillier by the second.

They saw Xavi too -- or could have sworn they did -- on Wednesday night when Barcelona played Tottenham at the stadium where they won their first European Cup in 1992 and their finest 19 years later, the purist expression of an identity. Familiarity grew with every minute until there was a moment it really registered: Arthur turned right around and Victor Wanyama followed him through the full circle, but was destined to never get there, the ball always blocked by the Brazilian midfielder's body. It's him, it's really him, they thought.

The reaction to this revelation was almost nostalgic, as well as needy, like they were trying to reach for something, someone, who had gone. It might not be helpful, but it could not be helped. The movement, the inclination of the body, even its shape: a centimetre taller, three kilos heavier, but not so different. The positioning and awareness, when to stop the ball, when to let it go by, which pass to play, the willingness to wait for it, to resist in the meantime, the 68 passes completed of 75 attempts.

And that turn; that was Xavi. Round he goes until the opponent has gone, wriggling free as passing avenues open. Right there, they saw him, wearing No. 8. They were not the first to do so; Messi had before.

"If I have to mention one of [the new signings], I'd say Arthur, who has surprised me because I didn't know much about him," Messi said in the summer. "There are differences, but he has a style very like Xavi's: he always wants the ball, he doesn't lose it, he plays it short, he's very reliable, very secure."

Then there is this: "He's a footballer who is perfectly adaptable to Barcelona, he has what we call the Barcelona DNA, that technical quality, the talent necessary to be a success. In terms of his qualities, I don't have any doubt that he could be a great player for Barca. He has all the qualities you need for that."

Who said it, also in the summer? Xavi himself; not just the midfielder at the heart of that Barcelona team, but a kind of ideologue and defender of a footballing faith, protecting and projecting a very particular view of what the game -- Barcelona's game -- should be.

Arthur arrived from Gremio for €30 million in July, aged 21 and having only made his competitive debut a little over a year earlier.

"He grasped the training sessions very quickly and the idea of a short game," Messi said. "That's something that tends to be hard for those who come from outside, but he grasped it fast. He has the style they have always looked for at this club."

Arthur shows great promise but Barcelona fans must not get carried away just yet. Photo by Xavier Bonilla/NurPhoto via Getty Images

Former sporting director Robert Fernandez insists that, to play for Barcelona, "you have to know how to use your neck to look all around you," adding that it was essential to master the control orientado (moving as you control the ball rather than after you've controlled it).

The words are reminiscent of comments from Xavi in February 2011, when he not so much answered questions as delivered a manifesto, leaping to his feet to demonstrate, shuffling his body round, an invisible ball at his feet, head swinging from side to side.

"Think quickly, look for spaces," he said. "That's what I do: look for spaces. All day. I'm always looking. All day, all day. Here? No. There? No. People who haven't played don't always realise how hard that is. Space, space, space. I think 's---, the defender's here, play it there'. I see the space and pass. That's what I do. "Think, think, think. Quickly. Lift your head up, move, see, think. Look before you get the ball. If you're getting this pass, look to see if that guy is free. Pum."

It was tempting to look at Arthur's stats vs. Tottenham -- 13 passes to Messi, 10 to Philippe Coutinho --and recall Xavi talking about how he liked to distribute the ball, ensuring everyone got it -- Messi especially -- and staying aware of who he passed to and how often, as if a calculator was an essential part of his kit, alongside boots and shin pads.

Arthur grew up watching Xavi and Andres Iniesta: "They are the 'mirror' I look in," he said. Role models, an aspirational image. It was their intelligence that struck him, Arthur says, the turn. He practiced it in the hall of his house, knocking the ball against the wall, controlling and changing direction in one go.

On Wednesday, it was not the wall, it was Wembley. Location feeds into the response, exaggerating it, while so too does the moment: After three games without a win and four years without a Champions League title, it was as if Barcelona were lost, only to find themselves on their biggest night so far this season.

In just his second start for the club, it was as if they discovered Arthur as well. London was not just where they thought they found a good player, although it is too early to know just how good, but the right kind of good player, with "the style they have always looked for at this club," as Messi put it. It is a style that in recent years has not been so obvious and one that, contrary to the captain's words, some doubt they have truly looked for lately, amid fears the club was losing its religion.

Xavi's style, Barcelona's style.

Check your timeline from Wednesday night: Search "Arthur, Xavi, reincarnation" on Twitter and you will see some were getting tearful; this meant something more than a match. For some fans at a club where identity matters and is fought over, it is their very being.

"I've always admired Xavi and it makes me very happy to be compared to him because he was Barcelona's constructor," Arthur said.

"It's like he came out of La Masia," Marca wrote, referencing the iconic old farmhouse that stands alongside the Camp Nou, where youth teamers lived and had their identity forged in all things Barcelona. It is empty now; a symbolic, seemingly telling fact not lost on anyone. "He smells of La Masia", El Mundo Deportivo said. Here was a Barcelona player, even if he had to be bought. "Arthur turns like the best Barcelona midfielders," said El País.

Friday morning's Sport leads on "Arthur, Xavi's apprentice," adding he has Barcelona DNA and, like many others, is "the New Xavi". Perhaps they should not. No one should. The excitement is understandable, but that does not necessarily make such comparisons advisable. And not just because this was a single game, one that risks being exaggerated and that, in truth, was marked more by Messi and Busquets than by Arthur. It is not advisable because of everything else it brings.

Asked in the summer what he thought about comparisons with Arthur, Xavi replied: "I don't like it. I didn't like people comparing me to [Pep] Guardiola. It's not easy to take on, not easy to digest; it's a millstone you carry on your shoulders and that's not good. He has to build his own career, show that he is a different player and if we leave him alone, he will succeed. But it's very hard at Barcelona, very hard."

Xavi knows. It is often forgotten that his style was not always universally embraced, that he was doubted and told football had moved on. He lived with the pressure of following Guardiola, saw the pressure loaded on Andres Iniesta to follow him and read those who said they couldn't both play in the same team -- "How did that go?" he said with a laugh. If Xavi became a determined defender of a certain identity, an ideologue, there was a reason: "It was that or die," he said.

"People discovered me since Euro 2008," Xavi once said. He was 28 then, some six years older than Arthur is now. In the 10 years since, football has shifted again and so have Barcelona: Xavi left in 2015; this summer Iniesta followed. Arthur followed both and the risk is that he is projected not just as a great player but the player to inspire a revival, to bring them back. His performance at Wembley rekindled an old flame, an old idea, igniting hope. It is a lot of responsibility to shoulder, even if ultimate responsibility will always be borne by Messi.

On Wednesday night, for a moment, Arthur turned away from his opponent and into Xavi Hernandez; care must be taken to ensure that is not turned against him.