And just seconds later, Wijnaldum sent Anfield into delirium with another to level the score on aggregate.

"Blimey. What are we witnessing here. All square," BT Sport presenter Gary Lineker tweeted, while Ian Wright simply posted 22 'screaming in fear' emojis.

Former Liverpool player Luis Garcia posted: "I have seen this move too!!" referring to his own part in the Reds' comeback against AC Milan in 2005, when they came from three down to win the final on penalties.

With just 12 minutes of normal time remaining, Liverpool's Trent Alexander-Arnold displayed cunning to send Origi through from a corner, and the forward duly scored the decisive goal to send Klopp's team through to their second consecutive Champions League final.

Louis Theroux, who has observed some unusual circumstances while filming documentaries, could not believe his eyes, tweeting: "Whaaaaaat?"

Former Barca midfielder and youth product Cesc Fabregas took to social media to praise Alexander-Arnold's quick thinking.

"Alexander-Arnold, 20 years old. People will tell me it's bad defending, I'm telling you it's pure intelligence and vision," he wrote.

Jermaine Jenas, meanwhile, heaped praise upon the youngster, tweeting: "Didn't think I could be anymore impressed by Trent Alexander Arnold such a brilliant young intelligent footballer!" and Peter Crouch simply wrote: "How old is @trentaa98? That was a joke."

By the time the final whistle came, Anfield could hardly contain its excitement.

"IT'S A MADNESSSSSS!!!!! #YNWA" Alex Oxlade-Chamberlain posted.

Former Reds forward Stan Collymore shared an image of a Barcelona tweet, commenting: "Messi! Cruyff! Pep! Gaudi! Joan Miro! Salvador Dali! Your boys took one hell of a stuffing!!!"

Loris Karius, who played in goal for Liverpool in the Champions League final against Real Madrid last season, tweeted: "This is Anfield! So happy for club & fans! #YNWA".

And in typical fashion, Champions League winner and Liverpool legend Jamie Carragher simply tweeted his colleague and Manchester United alumnus Gary Neville with a 'man shrugging' emoji.

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