THEY really thought they had seen the lot.
St Etienne in ‘77, Stevie G’s scorcher against Olympiacos in 2004, Dejan Lovren’s winner against Borussia Dortmund in 2016 were all great nights. Nothing tops this.
Liverpool, three down from the first leg against five-time European Cup winners Barcelona, scored four without response.
It is a breathtaking, jaw-dropping comeback.
Divock Origi and substitute Georginio Wijnaldum both scored twice to take Liverpool storming back towards next month’s final.
This manner of this frenzied victory muscles in on Istanbul, when Liverpool recovered from 3-0 down in the 2005 Champions League final to beat Milan.
They lifted the trophy that year and they are threatening to win it again.
At the final whistle this place was rocking, with Liverpool supporters daring to dream of winning the thing for a sixth time in Madrid next month.
It is on for them, it has to be.
Finalists last season, Liverpool will believe they can go one step further after this riotous Anfield night.
It is amazing to think that they did all this without Mo Salah and Roberto Firmino.
The clincher arrived 11 minutes from time when Trent Alexander-Arnold mugged off the entire Barca defence from a corner.
With those fluorescent shirts turned, he returned to take it quickly to send it into the swinging boot of Origi.
Liverpool’s back-up striker took the chance with a clinical, ruthless forward’s finish.
DAVE KIDD Reds' historic night was down to the squad players – typical of Klopp
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There was no way back for Barca.
They were done, giving a thorough working over by this extraordinary Liverpool side.
Their powers of resilience, their ability to drag themselves back from 3-0 down, is already the stuff of legend
If they win it, these boys will be remembered in the same way as Dalglish, Souness, Keegan, Stevie G and Carra.
Seven minutes in, they started to believe.
Origi, matchwinner against Newcastle last Saturday, shook the Kop with the opener.
Liverpool had been charging around, leaving a foot in here and there as they tried to unseat Barca.
They did just that when Origi scored, tapping in from close range after Jordan Henderson forced his way into the area.
Jordi Alba had made the uncharacteristic mistake, failing to clear Joel Matip’s raking crossfield pass to Sadio Mane.
A few touches later, with Mane, Henderson and Origi joining up the dots, Liverpool had taken an early lead.
Barca were rattled, with this crazy spell causing alarm and panic in those opening minutes.
Andy Robertson will not care, but he will be embarrassed when he looks back on the moment he gave the GOAT a disrespectful off-the-ball shove on the back of his head. Can’t be doing that.
The left-back, who clashed with Suarez in the Nou Camp defeat, was forced off at the break.
The substitution turned out to be an unexpected masterstroke.
Anfield, sensing the anxiety flooding through this Barca side, crackled with anticipation.
It was brooding in there.
The oppo had been clawing their way back into it, with Messi sniffing around the penalty area in search of No601.
Alisson saved well from the Little Master and Joel Matip pinched the ball of his toes on the edge of the area in another move.
Then Messi turned provider, waiting for Philippe Coutinho to steam in from the left to sidefoot an effort towards Alisson.
There was danger everywhere.
Sergio Busquets was booked just before the break, launching himself through the air to nobble Fabinho.
It was that kind of night, with players threatening to take their petty little squabbles to another level.
Champions League football stirs passions, with this intoxicating second leg firing up these Liverpool players.
They needed another at the start of the second half, the goal that would drive them towards this unforgettable victory.
Virgil van Dijk nearly got it, denied by the quick-witted response of Marc-Andre Ter Stegen when he turned away his chance on the half-turn.
Barca did not survive much longer.
Klopp’s boys were on to something, convinced they would get the goals to knock out these storied superstars from Spain.
What happened next turned out to be 31 seconds of heaven.
That was the time between the kick-off after Liverpool’s second and the moment Wijnaldum’s header rippled the nylon of Ter-Stegen’s netting for the third.
His first arrived after Alexander-Arnold sent in a low, angled cross that was drilled in to make it 2-0 by Wijnaldum.
He had only been on the pitch since the start of the half, pressed into action when Robertson was done.
It was turning into his night.
His next came 56 minutes in, with Milner working the angle for Shaqiri to cross for him.
The leap was spectacular, powering his header beyond the static figure of Ter Stegen.
It was all on after that.
There was only one winner in town, with Liverpool sending men forward in search of a fourth before the 90 were up.
They got it when TAA sent in his quick-witted corner for Origi to smack emphatically past Ter-Stegen.
Liverpool barely had time to catch their breath before the enormity of this started to kick in.
Whatever happens in the final against Ajax or Tottenham, they have just played their part in Anfield’s greatest game.
After this, their name is already on the trophy.