When Spain named a 16-year-old in the starting line-up for their opening match of Euro 2024 against Croatia, the reaction of some viewers across the world was: 'Who?'
By the half-time whistle, Lamine Yamal was the hottest young star in world football, lighting up a dream opening period which saw Luis de la Fuente's side surge to a 3-0 lead thanks in no small part to the winger's daring runs and a pinpoint cross to set up Dani Carvajal.
That day he became the youngest player to feature in the tournament and, unsurprisingly, the youngest to provide an assist. And the records have not stopped there.
By the time he lifted the trophy at the end of a breakout month, Yamal had seized the records for youngest goalscorer, youngest assister in a major final, and cruised to the Young Player of the Tournament prize.
He is currently leaving the Premier League's litany of young talents in his wake, as reflected in his gobsmacking £180.9million (£150m) value according to CIES Observatory, but there are several prodigies who might catch up with the Spaniard in years to come. Here, Mail Sport brings you the under-21 stars vying for Yamal's crown.
For now, the Barcelona winger seems unstoppable and he was rewarded with the Golden Boy award at the Ballon d'Or ceremony in Paris.
Yamal is comfortably the youngest player in the top 20, and indeed the youngest on the entire list of 100, and is worth over 50 per cent more than the man in second place.
Despite Manchester United's woes this season, their future stars feature heavily in the countdown, and leading them is Argentinian wonderkid Alejandro Garnacho.
The 20-year-old has had a mixed start to the current campaign, with just one goal involvement in his last six league matches, but his habit of a wondergoal as well as his pacey dribbling has wowed fans across the world and he is valued at £95m.
Defensive midfielders have in the past been undervalued but it seems a new era is dawning with the number six after Man City's Rodri scooped the Ballon d'Or at the expense of more attacking stars.
Continuing the trend, France and Paris Saint-Germain's Warren Zaïre-Emery, 18, is the third most valuable young player in the world at £90m. His teammate Joao Neves is in fifth, with the Portuguese being worth a whopping £83m.
Sandwiched in between is City talent Savinho, who has been given a chance to shine this season by Pep Guardiola, assisting five times in 14 appearances in all competitions.
The Premier League champions' No 26 has drawn comparisons to the old inhabitant of his squad number, Riyadh Mahrez, with his jinky runs and wand of a left foot. If he has half the career of the Algerian, his value of £84m will continue to skyrocket.
A devastating future Real Madrid front line comes next with Brazil's Endrick, worth £81m, and Turkey's Arda Güler, £63m, recognised for their dazzling form.
Endrick has been mesmerising in a Selecao shirt in his short career, scoring a memorable goal against England at Wembley, but the 18-year-old has been consigned to a limited number of substitute appearances this season for his club.
Guler, 19, has experienced the same frustrations under Carlo Ancelotti this campaign despite scoring arguably the goal of the tournament against Georgia at Euro 2024.
In between the Los Blancos pair is another City man. Rico Lewis has consolidated his position as the side's first-choice right-back, playing nine matches in the Premier League so far.
The 19-year-old, worth a substantial £72m, has even earned consecutive call-ups for the England national team this campaign.
Kobbie Mainoo, 19, worth £62m, went from strength to strength in the 2023-24 season, starring in a win over Everton in November 2023 before scoring a wondergoal against Wolves in February 2024.
The centre-midfielder became a mainstay in the United side, turning in a man of the match display in the FA Cup final against rivals City. He then broke into the England side during the Euros and played in all of their knockout phase matches.
Juventus and Turkey's Kenan Yildiz, 19, makes up the top 10 with a value of £60m while PSG's Lucas Beraldo, 20, just misses out. The Brazilian centre-back is worth £58m.
Aston Villa super-sub Jhon Duran, 20, has fired his way into the prestigious list thanks to a flurry of goals from the bench for Unai Emery's men, including an iconic winner against Bayern Munich in the Champions League last month.
The Colombian's form mean he is now also valued at £58m, with his stock only rising.
Brighton pair Evan Ferguson and Carlos Baleba, both 20, also feature in the top 20, evidence of the attention the Seagulls have paid to recruitment in recent years.
Ireland's Ferguson scored his first goal in 11 months in a 2-2 draw against Wolves last month but is still highly valued at £51m.
Baleba, meanwhile, is a relatively new face in the Brighton starting line-up but has caught the eye and the Cameroonian is now worth £43m.
Leicester's mercurial attacking-midfielder Facundo Buonanotte is worth £48m thanks in no small part to three league goals already this season. He is another feather in the Seagulls' cap and will return to the Amex next summer after a loan spell.
Bayern Munich duo Mathys Tel, 19, and Aleksandar Pavlović, 20, also break into the top 20, valued at £48m and £45m respectively.
Despite picking up an injury almost the moment he walked through the door at Old Trafford, French defender Leny Yoro is still worth £45m after his summer move from Lille.
Who knows what he will be valued at when he actually gets on the pitch.
Atalanta centre-back Giorgio Scalvini, worth £54m, and Borussia Dortmund's English winger Jamie Bynoe-Gittens, valued at £48m, complete the top 20.
Five Chelsea players make the top 100, including three of their myriad loan players.
However, their most expensive youngster, Romeo Lavia, does not even make the top 50 and is worth just £25m despite the Blues paying £53m for him in August 2023.
Neither Liverpool nor Arsenal, meanwhile, boast a single player in the list.
Yamal continues to lead the way after a coming-of-age 2024 but do not be surprised if we see a Premier League star burst on to the scene and rival him for Ballon d'Ors in years to come.