Ajax stunned Juventus to reach the Champions League semi-finals for the first time since 1997 as Matthijs de Ligt's thumping second-half header secured a 2-1 second-leg victory in the last eight in Turin on Tuesday.
Cristiano Ronaldo, bidding for his sixth Champions League title, scored a 28th-minute header to put Juve ahead after a 1-1 first-leg draw, but Donny van de Beek levelled for Ajax before half-time.
Teenage centre-back De Ligt struck midway through the second period, though, to seal a 3-2 aggregate win and set up a last-four clash with either Manchester City or Tottenham.
The young Dutch side had already eliminated three-time defending champions Real Madrid en route to the quarters, overturning a 2-1 home defeat against the Spanish side with a memorable 4-1 victory at the Santiago Bernabeu.
"It's an incredible evening for Ajax and its players and also for Dutch football," said coach Erik ten Hag.
"Once again we eliminated the favourites.
"We said before we were not the favourites but with our philosophy we can go further, we've again surpassed our limits."
Juventus had been looking to reach the Champions League semi-finals for the third time in the past five seasons.
But Ronaldo, who scored an away goal last week with a diving header in Amsterdam, was Juve's only weapon against the impressive Dutch side.
The 34-year-old was signed for 100 million euros ($117 million) last summer from Real Madrid in a bid to win the European trophy for the first time since 1996, when they beat Ajax in the final.
"Ajax deserved to qualify," said Juve coach Massimiliano Allegri.
"We could have done better, but Ajax aren't coming out of nowhere, they were Europa League finalists two years ago and scored five goals against Real.
"It's not our worst elimination. We had big expectations, but the Champions League is a strange competition. You have to arrive in peak condition.
"In the last month we have been struggling with several injuries. Even tonight we were missing important players."
Juve forced to reshuffle
Allegri had been forced to reshuffle his side because of injuries, with Paulo Dybala returning in place of the injured Mario Mandzukic, while captain Giorgio Chiellini was also sidelined.
Ajax's defence took a hit when Noussair Mazraoui, who had replaced the suspended Nicolas Tagliafico, limped off on 11 minutes with an ankle injury, with Daley Sinkgraven coming on.
Ajax goalkeeper Andre Onana dived to keep out a scorching Dybala half-volley in the 20th minute.
But Ronaldo latched onto a Miralem Pjanic corner with a downward header that left Onana with no chance.
It was the Portugal star's 126th Champions League goal and sixth of this campaign, having now scored in his past six European games against Ajax, netting nine goals in total.
But Van de Beek soon silenced the cheers of the home crowd when he controlled a wayward Hakim Ziyech shot six minutes later, rolling the ball past Szczesny to cancel out Juventus' away goal and make it 2-2 on aggregate.
Teenage striker Moise Kean replaced Dybala after the break, but it was the Dutch who turned on the style, with only Szczesny's reflexes keeping Juventus in the tie.
The Polish keeper denied Ziyech from close range with one hand, and minutes later tipped Van de Beek's curling effort over the bar.
The Juventus back-line struggled with the pace of the Dutch team with Pjanic doing well to deny Ziyech a tap-in.
But Ten Hag's side's incessant pressure paid off with 19-year-old skipper De Ligt towering above Alex Sandro and Daniele Rugani to head home Lasse Schone's corner on 67 minutes.
Ziyech looked as if he had fired a third past Szczesny, but his goal was ruled offside after a VAR check.
And the Dutch visitors held on, with Ronaldo unable to make a difference after his incredible hat-trick had pulled Juventus into the quarter-finals in the last-16 win over Atletico Madrid.
Four-time winners Ajax won their third consecutive title in 1973 at the expense of Juventus, and last lifted the trophy in 1995, with their last semi-final appearance ending in defeat by Juve 22 years ago.
Juventus now turn their focus back to Serie A where they can win an eighth consecutive title on Saturday.
"Ronaldo had a good match, he scored. He's disappointed like all of us," said Allegri. "Saturday we have to close out the Scudetto."
Careless United undone by Messi double as Barca cruise into semis
Lionel Messi pounced on two Manchester United mistakes to score twice and end their hopes of another comeback at Camp Nou as Barcelona breezed into the Champions League semi-finals on Tuesday.
After an excellent start, United were undone twice in four minutes by Messi, who first nicked the ball off the careless Ashley Young and then watched as a weak shot from distance squirmed underneath David de Gea.
Philippe Coutinho, in perhaps his best performance of the season, added a third with a curling effort into the top corner and by the end, an outclassed United might have been relieved the score was not more traumatic than 3-0, 4-0 on aggregate.
"We had five uncomfortable minutes because they came out strong," said Barcelona coach Ernesto Valverde. "But then there were another 85 minutes where we weren't bad."
A dizzying opening spell, in which Marcus Rashford had hit the crossbar, was long-forgotten, even if it could offer Barca's next opponents some encouragement.
Liverpool, who take a 2-0 lead to Porto on Wednesday, are now the most likely obstacle between them and their first Champions League final since they last won this tournament in 2015. Mohamed Salah and Sadio Mane might feel emboldened.
Instead, United's pair of early errors made this another night about Messi and ensured any faint hopes of repeating the comeback against Paris Saint-Germain, or even the famous 1999 rescue act against Bayern Munich, on this same pitch, were dashed.
"We said all along this was not going to change overnight," United's coach Ole Gunnar Solskjaer said. "In the next few years it is going to be a massive effort to get to the level of Barcelona and these sorts of teams."
Messi now has his 109th and 110th Champions League goals and, potentially, three extra matches to reduce the gap on Cristiano Ronaldo's 126, after Juventus were dumped out by Ajax. Barcelona's fans celebrated that too.
Solskjaer had urged his strikers to be more lethal here but it felt ominous that even before kick-off, Rashford, Anthony Martial, Romelu Lukaku and Alexis Sanchez had hit 42 goals this season, while Messi on his own had 43.
Around an hour before kick-off, Alex Ferguson was on the side of the pitch, shaking hands with Ryan Giggs and sharing words with Solskjaer, the scorer of the winning goal against Munich here 20 years ago.
They could have hardly have asked for a better start. United were brilliant for eight minutes and could have been ahead within 30 seconds as Rashford raced onto a curving Paul Pogba pass and toed away a shot, which Marc-Andre ter Stegen bravely left to graze his own crossbar.
Barca were flustered, so much so the crowd even cheered with relief when Arthur Melo played his team's first convincing pass.
Then, Barcelona had their own eight-minute flurry as United almost conceded a penalty, ruled out after Fred took the ball before bringing down Ivan Rakitic, and then did concede, twice, to Messi.
Both could have been avoided, even if Young's turn on the edge of his own box was punished in devastating fashion. Young lunged in to atone for his mistake but Messi skipped away from him, poked it through Fred's legs and then whipped the ball into the corner.
The second was simpler. Fred and Scott McTominay closed in on Coutinho and the ball spilled out to Messi, whose dribbling shot with his right foot should have drawn a routine save. Instead, De Gea let it squirm under his body for 2-0.
Pogba lashed out at the increasingly influential Arthur and Barca could have had a third before half-time, De Gea scrambling across to save on the line when Sergi Roberto should have finished.
Messi could have had his hat-trick too after Luis Suarez found him with a superb cutback and there was an almost comical sequence in the second half when the Argentinian played with his United chasers before finally being bundled over by McTominay.
Rashford might have made it interesting if he had controlled Pogba's ball over the top but Barcelona were in exhibition mode, helped by a vintage Coutinho curler after he had cut inside from the left.
Messi even attempted a bicycle kick and there were celebrations from the home fans when news went round that Ajax had taken the lead in Turin. They believe this is their year.
Updated Date: Apr 17, 2019 09:12:37 IST