The rainbow flick came about half an hour into the game, and in all fairness to Vinícius Júnior, it’s not like he had a plethora of superior options. Pinned to the left touchline, two Uruguay defenders in attendance, no Brazil teammates coming to help him out. And so, with a flash of improvisation, a little flick of the left heel and a burst of speed, he was away and clear: an outrageous piece of skill that would – nitpicking here – have been even better had he actually managed to take the ball with him.

In a way this little vignette, clipped from a bruising 2-0 World Cup qualifying defeat by Uruguay in October, sums up Vinícius’s international career to date: big plans and big ideas thwarted. It’s five years since he made his debut, and in that time a global star at under-15 and under-17 level has matured into one of the sport’s great forwards. But in Brazil yellow, at least, the great leap forward is yet to materialise.

He still has only three international goals in 26 caps, has only twice completed 90 minutes in a competitive game. Over the past three seasons at Real Madrid, he has averaged a goal or assist every 101 minutes in all competitions. For Brazil, it’s every 205 minutes. And as Vinícius prepares to step out at Wembley on Saturday night, the failure to reproduce his stunning club form at international level remains one of the enduring puzzles of this mercurial Brazil side.

For his part, Vinícius has noted the incongruity. “I have been very bad in the last few games, I have a lot to improve,” he admitted after that Uruguay defeat. “My cycle with the national team has not yet been what I expected. I have a lot to evolve to be able to play the best I can, like I do in Real Madrid.” And yet for all his admirable self-reproach, Vinícius has also partly been the victim of circumstances. In a way, his tale is a parable of the modern Brazil team, a team that for most of this century has struggled to exceed the sum of its parts.

There are mitigating factors, of course. Hamstring and thigh injuries have hampered him this season, to the extent that Vinícius missed half of Brazil’s dire World Cup qualifying campaign in the autumn. The farcical carousel of coaches – with Tite being replaced by Ramon Menezes being replaced by Fernando Diniz being replaced by Dorival Júnior in the space of 13 months while the national federation forlornly pursued Carlo Ancelotti – has generated a kind of internal bewilderment, in which nobody really knows Brazil’s best team or optimum system any more.

Take the six games Vinícius played for Brazil last year. The measured 4-3-3 of Menezes gave way to the hectic 4-2-4 of Diniz, with Vinícius himself shuffled from left wing to centre-forward amid a rotating cast of forwards. Rodrygo, Gabriel Jesus, Richarlison, Antony, Malcom, Rony, Vitor Roque, Pedro, Raphinha, Gabriel Martinelli: these are the men with whom Vinicius has shared the Brazil front line in just 12 months.

Of course, there’s one other player on that list, perhaps the most pivotal of all. Neymar is often blamed within Brazil for stifling Vinícius’s development: a little unfairly, given that Vinícius has misfired without Neymar as often as he has misfired with him. But this is still a Neymar-esque team, even as the man himself enjoys his lucrative Saudi sinecure: a shrine to individual talent, brilliant players often left to fend for themselves in the absence of meaningful relationships and drilled patterns on the pitch.

At Madrid, Ancelotti has designed a system to get the best out of Vinícius: keeping him high up the pitch, whittling his game down to its sharpest points. With Brazil he is often forced to wander and roam in search of the ball, forced to make things happen himself, starved of service in his favourite areas. The most damning stat: this season Vinícius averages 3.44 shots per 90 minutes for Real Madrid, and just 0.95 for Brazil.

With Neymar’s career in sharp decline, Vinícius has gradually usurped his status as the biggest star in Brazilian football. The racism he has suffered while playing for Madrid has generated a strong wave of sympathy and recognition in his home country. And yet until the Qatar World Cup, he was not even a guaranteed starter: the night before Brazil’s opening game against Serbia, Tite’s coaching staff were debating whether to put him in the XI.

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Of course Vinícius is first choice now, and the arrival of Dorival – a less dogmatic and more flexible coach than his predecessor Diniz – offers a fresh start of sorts. The age of Neymar is almost over – he is recovering from ACL surgery and will be 34 by the 2026 World Cup – and so there is a broad consensus that Brazil need to rebuild around the youth of Vinícius, Endrick and Rodrygo.

Still, with the Copa América just three months away, the clock is ticking. It feels ridiculous to suggest that a player who scored the winning goal in a Champions League final at the age of 21 still needs to prove himself on the big stage. For Brazil, however, there is a kernel of truth there. And if being the best player on the world’s most celebrated international team comes with certain expectations, then at least he has plenty of time to meet them. “The emotion is as if it were the first time,” Vinícius said on arriving in London for his call-up. To all intents, it may as well be.