When Ajax beat Borussia Dortmund home and away during the group stages of the 2021-22 Champions League, it was not only significant in terms of the European fates of two of the continent's biggest clubs.
It was a battle between two sides whose reputations of late have been built on their ability to develop young players, and whom some would consider as being the teams that have the best conditions and in-built pathways for elite talents to make their way into first-team football anywhere in world football.
That Ajax came out on top on both occasions was, then, a feather in the cap for the Dutch outfit, while those victories also allowed them to get a slither of revenge over a club whom they feel they lost out to over the negotiating table earlier in the year as regards to one of Europe's top teenage strikers.
Back in January 2021, Julian Rijkhoff celebrated his 16th birthday by leaving Ajax - a club he had been at for the past nine years - to join Dortmund in one of the more eye-catching transfers of a player that age in recent times.
Regarded as one of the hottest prospects within the famed Ajax academy at the time, Rijkhoff rejected the chance to sign a professional contract at the Johan Cruyff ArenA after being left unimpressed by how long he would likely have to wait to earn a chance in the senior squad if he remained in Amsterdam, particularly following the signing of Sebastien Haller from West Ham earlier that month.
Rijkhoff had one year previously marked his Ajax U17s debut with a goal on his 15th birthday, before going onto score 10 goals in six games at that level between various Covid-enforced shutdowns.
He felt, though, that the grass would be greener in Germany, and Dortmund were willing to pay €130,000 (£115k/$158k) to bring him to Signal Iduna Park.
Netherlands legend Marco van Basten criticised the deal, hitting out at Rijkhoff for having "very bad management", though the youngster's agent was keen to highlight why his client was so keen to move on.
"We were very impressed in the talks. Dortmund knew everything about him, their scouting department did a very good job," Dick van Burik said following the transfer's confirmation.
"How well BVB already knew him, how he was developing and how convinced they were of him - all of this made a great impression on Julian and his parents."
For Rijkhoff, the criticism was nothing new despite his supreme talent, and he has not looked back since arriving at the Dortmund academy.
"There was a lot of excitement. That it turned out that way, especially on social media, surprised me," Rijkhoff, who rose to notoriety when he scored six goals in three games for the Netherlands U15s during a tournament in Spain in early 2020, told ELF Voetbal.
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"From an early age, I was used to getting comments about my appearance, especially when I still had long hair. I let them pass me by, just like what was written in the media.
"The people who know me are close and know why I chose Borussia Dortmund."
Coronavirus and a torn ankle ligament suffered in March meant that Rijkhoff did not make his debut for the Bundesliga outfit until the start of the 2021-22 campaign, but he has become an integral part of the club's successful U19s side in the early months of the season.
It was expected that Rijkhoff would start off with the U17s, but his ability is such that he was immediately thrown into Mike Tullberg's side, where he has formed a fearsome strike partnership with Swiss forward Bradley Fink.
Tullberg's team were the only German side to qualify from the group stages of the UEFA Youth League - where a 5-1 win over Ajax in Amsterdam helped them on their way - while they are also top of the U19s Bundesliga West table, in the semi-finals of the U19s DFB-Pokal and have already won the regional League Cup after a double from Rijkhoff in the final secured a 2-0 win over arch-rivals Schalke.
In total, Rijkhoff has returned 17 goals and five assists from his first 20 appearances in a Dortmund shirt, but it is not just his record in front of goal that has caught Tullberg's eye.
"What is pretty impressive about him is his physical attributes and the way he has come in on that regard since he got here," Tullberg tells GOAL and SPOX in an exclusive interview. "In our last game, he ran almost 12 kilometres. You rarely see that with a striker, even among the professionals.
"That included around 300-400 metres of sprints, too. These numbers are among the best in our team, and you can't tell that he is actually still an U17 player."
On the ball, it is easy to see why Rijkhoff was a target for a number of European clubs before Dortmund made their move, with the his excellent ball control and instinctive finishing marking him out as a standout among his peers.
He counts Robert Lewandowski - who he has sometimes been compared to - and Erling Haaland among those he looks to learn from, with that particularly clear when he drops into the half-spaces in front of the opposition defence so as to play a role in Dortmund's build-up play.
Despite his physical gifts, Rijkhoff has at times struggled with the intensity of German youth football compared to what he was used to at Ajax, where there is more emphasis placed on the technical side of the game.
"All in all, he had a few normal highs and lows," says Tullberg. "First, he had to come to terms with the fact that he had to prove himself here.
"He sat on the bench a few times or was replaced at half-time, something he had never experienced in his previous footballing life. To stay in the team, he had to adapt to the intensity that we have in training and games, but he took to the challenge well."
Rijkhoff reaped the rewards from his hard work during the final weeks before German football's winter break, as his brace in the cup final win over Schalke sparked a run of four games during which he scored nine times, including a five-goal salvo against Dusseldorf.
"I said to him: 'You are getting the chances, so now you just have to take them'," recalls Tullberg. "He looked at me very calmly and said, 'Don't worry, coach - goals are my specialty!' I found that very impressive.
"Then he went and scored nine goals in no time. His greatest weapon is scoring goals."
So what comes next for Rijkhoff, one of the best 2005-born strikers anywhere in the world right now?
There is something of a queue that has formed behind Haaland in the Dortmund striker pecking order already, with fellow teenager Youssoufa Moukoko still waiting for his chance to play regularly under Marco Rose, while Fink - who is two years Rijkhoff's senior - has 33 direct goal involvements from his 20 U19s appearances this season, and as such will be keen to earn a promotion sooner rather than later.
For Rijkhoff to challenge them in the next year or so, he must continue to develop the aspects of his game that do not always come as naturally as general ability when in possession.
"He is already able to think fast, but he needs to be even more ahead of his opponents mentally so he can beat them across 10-15 metres going forward," Tullberg explains.
"He also has to be more robust overall. For example, when it comes to controlling the ball with his back to goal, if his opponent plays a bit more physically, you can tell that he is not always able to counter it.
"But that comes slowly. He's still young, but very willing to learn."
And it is for that reason that while Ajax might have won the battles this season, Dortmund may well have won the war if Rijkhoff delivers on his potential and fires them to greater glories in the coming years.