Last-minute winners, VAR making its debut in the knockout stages and the most unlikely of English finalists ... CNN Sport looks at eight epic matches which have captivated the world over the course of this most magical of seasons.
Eventual finalist Liverpool defeats PSG 3-2 courtesy of substitute Roberto Firmino's last-minute winner.
Firmino, who is nursing an eye injury after a gruesome incident in Liverpool's league win at Tottenham, comes off the bench to secure a crucial win that had looked in doubt after Kylian Mbappe's late equalizer threatened to rescue a point for the Parisians.
On the brink
The other finalist, Tottenham Hotspur, capitulates to a Lionel Messi masterclass at the home of English football, Wembley Stadium, as Barcelona wins 4-2 and sounds an ominous warning to the rest of Europe.
Spurs would later travel to the Camp Nou in the return fixture in the final group stage game, needing a result to reach the knockout stage -- and hope PSV Eindhoven could do it a favor against Inter Milan.
Just as things were looking bleak, Spurs found a late equalizer courtesy of a certain Lucas Moura ... and the rest is history.
This is Ajax's coming out party, as it produces a swaggering brand of swashbuckling football to shock three-time defending champion Real Madrid 4-1 at the Bernabeu to overcome the first-leg deficit and progress.
If Ajax's young, home-grown talent weren't on the radar of Europe's top teams before, they most certainly are now.
Ole's at the wheel
With interim boss Ole Gunnar Solskjaer in charge, Manchester United recovers from a 0-2 home first-leg loss to stun PSG in its own backyard with a controversial and dramatic injury-time winning from Marcus Rashford to send the Red Devils through.
It is another early exit from the under-achieving Parisians and, watching on from the sidelines, an injured Neymar is not impressed.
Not content with knocking out the holder, Ajax is at it again, this time against Cristiano Ronaldo and Juventus in Turin.
The Italian giant becomes the Dutch team's latest victim, as Donny Van de Beek and teenage captain Matthijs de Ligt score the goals to keep the fairytale run going.
Hip or hand?
The all-Premier League clash between Tottenham and Manchester City had arguably gone under the radar in the first leg, with the Londoners holding a slender lead.
But the script is ripped up in Manchester for the return leg, as the sides serve up an instant classic.
City's Raheem Sterling and Tottenham's Son Heung-min exchange a brace of goals each and Bernardo Silva and Sergio Aguero also net for the Blues.
A disputed strike scored off Fernando Llorente's hip gives Spurs a crucial lead on away goals but with time running out, Sterling thinks his hat-trick goal has put City through, only for VAR to rule out the goal for offside.
A spirited Liverpool had given their all in the first leg in Barcelona but Messi was the difference with his two late goals adding to Luis Suarez's opener.
But on another famous European night at Anfield, a pair of goals from the unlikeliest sources -- striker Divock Origi, who was only playing because of injuries to star starters Mohamed Salah and Firmino -- and substitute Georginio Wijnaldum turn the match on its head and send the Reds through 4-3 on aggregate.
The winning goal is something extraordinary. Wise beyond his years, local lad Trent Alexander-Arnold catches Barca off guard with his clever corner and Origi sweeps the ball into the net, and makes himself a Liverpool legend in the process.
Mour, mour, mour
The best is arguably saved for last as Tottenham, already down 1-0 from the first leg and now losing 2-0 on the night in Amsterdam, somehow produce possibly the greatest result in the club's proud history to score three second-half goals to advance to the final.
Brazilian forward Moura -- who much like Liverpool's Origi might only have been playing because of injury to talisman Harry Kane -- scores an historic hat trick, with the winner coming in the sixth minute of injury time, to break Ajax's young hearts and set up just the second all-English final in history.
The world awaits the Madrid final on June 1 between Tottenham and Liverpool, the outcome impossible to predict.
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