Ajax will have their latest crop of young gems at the Johan Cruyff Arena, where Frenkie de Jong and Matthijs de Ligt will attempt to live up to already-swelling reputations while the likes of Donny van de Beek, Andre Onana and Kasper Dolberg could also enhance theirs.
The surprise is less that Ajax's line-up will be sprinkled with emerging talents than the expectation Madrid's will be too.
Gareth Bale aside, the galacticos are gone, replaced by a handful of prospects trying to forge their own way through, only at the biggest and most demanding club in the world.
The shift was not so much initiated by the current coach Santiago Solari, whose predecessors Zinedine Zidane and Julen Lopetegui both used youth when they had to, primarily to rest key players or remind them their place was not guaranteed.
But in the biggest games, Zidane and Lopetegui were drawn to experience, while Solari has made youth first choice since being tasked with rejuvenating his team in November.
Vinicius Junior has had less time than Ajax's De Jong, with only six starts in La Liga and one in the Champions League, but his impact has been arguably just as dramatic, the hype around the Brazilian already comparable.
Signed last summer for 45 million euros, Vinicius was supposed to spend his debut season settling in with the reserve side, a strategy adhered to, perhaps too rigidly, by Lopetegui.
"He’s very young and has just arrived in Europe," Lopetegui said. "He’s very keen to learn and we’ve got to give him the time to settle that every player needs."
Solari, in charge of Real Madrid B at the time, was the coach that received him, witnessing first-hand as the 18-year-old scored twice against Atletico B, curled in a free-kick against Unionistas and equalised against Celta Vigo B.
Vinicius was raw but when Lopetegui was sacked, Solari had greater legitimacy to promote him. He had faith too. Solari gave Vinicius 90 minutes in his first match in charge, more than Lopetegui had in all 14 of his.
Almost four months on, Vinicius has 22 appearances for the first team, the latest pair against Barcelona at the Camp Nou and Atletico Madrid at the Wanda Metropolitano. In both, he was Madrid's greatest threat, to the extent that even Bale's starting spot has been questioned.
"His adaptation has been very fast," Solari said. "He is 18 and he has adapted to a new country, a new culture, a different type of football. He has shown his talent but we have to take care of him."
Vinicius is the poster boy of Solari's meritocracy, an approach that puts reputation far below humility and hard work.
Among those to lose out have been Isco, who is yet to start a league game under Solari, and Marcelo, whose form deteriorated at the start of the year. Casemiro has also been relegated to the bench.
Among the fresh faces to come in have been Sergio Reguilon at left back, the Spanish 22-year-old with a wand of a left foot, Marcos Llorente in defensive midfield, and Dani Ceballos, who could make the transition after Luka Modric slightly easier to bear.
Together, Vinicius, Reguilon, Llorente and Ceballos have played 64 games since Solari was appointed. "They are the future of Real Madrid," Solari said. "Therefore, they have to be part of the present."
But the present is now a strenuous few weeks when Madrid's season could be defined by matches against the best opponents, both in La Liga and Europe.
Jorge Valdano who, like Solari, played for Real Madrid, coached the youth side and then managed first team, said last month that youngsters should ideally be introduced gradually, allowed to bed in while more experienced players shoulder the responsibility.
Solari has had to fast-track his fledglings and so far that faith has been rewarded. Ajax, and the Champions League knock-out stages, is the next test.