Ajax have now turned football on its head twice. And if you would bet against them doing it a third time next month and a fourth time in June then you should start paying attention.
This is the greatest story in the modern history of the Champions League because it is entirely at odds with every other page of it. This is a proud historic club but a financially powerless one. David only killed one Goliath; Ajax have now killed two in six weeks.
Last month they beat three-time reigning champions Real Madrid 4-1 at the Bernabeu, a result applauded all over Europe in part because it felt like watching Halley's Comet, seeing a poor team outclass a rich team that comprehensively. But on Wednesday night in Turin, Ajax produced their second once-in-a-lifetime game, beating Juventus 2-1.
They should have won by far more given how they dominated the second half, playing football their richer opponents did not even dare, cutting through Juventus with every attack. But it did not matter, 3-2 over two legs was no real reflection but it was more than enough.
Ajax are now in the semifinals for the first time since 1997, back when they could still compete with sides like Juventus as equals, not financial inferiors. They could easily beat Tottenham or Manchester City over two legs if they play like this, and they could win the Madrid final on 1 June too.
But regardless of whether Ajax go on to repeat what they last did in 1995, they have already done something far more important than simply winning a competition. They have proven a point, and now proven it again.
Ajax's wage bill is less than the richer sides from England's second-tier, but they have turned that into a source of strength this year. They have a team of academy products and clever buys who are proving better than the big boys. Not because the individuals are brilliant -- although they are -- but because Ajax know that football is about being more than just a sum of your parts. It is about being a team. That is how they did the unthinkable to Real Madrid and now to Juventus, who paid Real £88 million for Ronaldo in the summer.
Ronaldo is the greatest individualist and he scored here, as he always does, giving Juventus a 2-1 aggregate lead. But he is no substitute for identity, coherence, team-work or belief.
His headers, one in each leg, were very good but they were also the full extent of Juventus' attacking play over 180 minutes of football. And after his goal Juventus did nothing else at all, as Ajax seized control and never gave it back.
Donny van de Beek equalised, Matthijs De Ligt headed the winner, and Ajax missed plenty of chances in a second half that was just as good as their one in the Bernabeu. In the end they dominated both legs and 3-2, in a tie where Juventus had two chances, barely scratches the surface.
"Can we can go on to win the competition? Well, we are in the semi-finals now. And we have eliminated two of the favourites in the last two rounds," Ajax skipper De Ligt said. "The next games will be very difficult, but so were these ones. So who knows? We don't know what we can achieve but we are never satisfied."