Yossi Benayoun scored a 15-minute hat-trick to break the hearts of a remarkable Havant and Waterlooville side who produced a sensational display at Anfield.
Twice the Hampshire non-leaguers were ahead against a shell-shocked Liverpool in this FA Cup fourth round tie.
Richard Pacquette and a Martin Skrtel own goal had Havant fans in dreamland. Lucas and Benayoun clawed Liverpool level before the break, with two more from Benayoun and a last-minute Peter Crouch effort seeing Liverpool home.
Liverpool boss Rafael Benitez took some of the glamour out of the tie by leaving Steven Gerrard, Fernando Torres and Jamie Carragher on the bench.
But the visitors still had to contend with Peter Crouch, Javier Mascherano and Jermaine Pennant, while while new boy Martin Skrtel made his full debut in central defence.
Havant boss Shaun Gale left assistant manager Charlie Oatway on the bench, while Tom Jordan - son of Portsmouth coach and former Manchester United striker Joe - started in front of a crowd which included around 6,000 fans from Hampshire.
Liverpool's fans applauded every single Havant player's name when they were announced, and the non-league club's fans sung happily along with 'You'll Never Walk Alone'.
Havant were undaunted early on - captain James Collins clattered Mascherano, Rocky Baptiste knocked over Sami Hyypia and Alfie Potter - Harry to his mates - saw a shot deflected wide.
Yossi Benayoun headed Pennant's cross wide, but Havant were intent on making their mark - and in the eighth minute they scored.
Richard Pacquette harassed Skrtel into conceding a corner, and when Mo Harkin planted it into the six-yard box, former QPR player Pacquette headed it powerfully past goalkeeper Charles Itandje.
Liverpool were stunned and while the Kop applauded loudly, the fans of the non-league club erupted.
For a while it was amusing for the home fans to see Liverpool embarrassed, but as the half wore on the Scousers started to lose patience.
John Arne Riise had two efforts blocked, Benayoun shot wide, but the anxiety grew as did Havant's confidence. Their set pieces constantly troubled Liverpool, goalkeeper Itandje was a bag of nerves and the tackles continued to thud in.
And Havant should have scored again after 23 minutes. Itandje twice fumbled as Harkin's free-kick flew wildly around the box and when the French goalkeeper fell over, Shaun Wilkinson hooked over an open goal from 10 yards.
Havant held their lead for 16 minutes of growing panic in Liverpool ranks. After 24 minutes, Ryan Babel laid the ball back to Lucas, and the Brazilian curled a fine goal into the top corner from 25 yards.
But incredibly, Havant were ahead again after half-an-hour. Steve Finnan stumbled over the ball on the right of the box and Potter, on loan from Peterborough, tore onto the ball and fired in a shot that Skrtel deflected wide of his own 'keeper.
Liverpool were a frightened shambles in defence, losing possession in midfield and seemingly incapable of passing the ball effectively.
Havant were magnificent. Organised at the back, they fought for every inch and outperformed their illustrious opponents. Carragher and Torres were soon warming up on the line.
Havant lost Phil Warner with a leg injury after 40 minutes they send on Tony Taggart, exchanging a binman for a plumber at the back.
A minute before the break Liverpool managed to claw themselves level. Pennant's pass set-up Benayoun, who created a yard of space to fire in a right-footer that gave Kevin Scriven no chance.
Havant started the second period deep in defence and they were giving Liverpool too much space.
And on 55 minutes they were punished. Mascherano surged through midfield before freeing Pennant on the right.
When his cross arrived in the box, Benayoun had time to turn and fire into the roof of the net.
Rocky Baptiste, the taxi-driving Liverpool fan, was withdrawn by Havant two minutes later, former Spurs youngster Jamie Slabber taking over.
Two minutes later Benayoun struck again to complete a hat-trick. Babel's shot came back off keeper Scriven and the Israeli was there to fire in the rebound.
After 72 minutes Dirk Kuyt replaced Benayoun and two minutes later Wilkinson went off, with Charlie Oatway taking over.
But the dream was over now for Havant.
Carragher eventually came on in place of Hyypia after 84 minutes, Gerrard following in place of Mascherano two minutes later.
There was still time for Neil Sharp to force a fine save from Itandje, but with a minute left Gerrard set-up Peter Crouch for a tap-in.