Second-choice goalkeeper Caoimhin Kelleher saved two penalties in the shoot-out which Liverpool won 5-4 against Leicester to send them into the semi-finals of the Carabao Cup.
Substitute Diogo Jota struck the winning spot-kick – having come off the bench to score in the second half – but the real hero was Takumi Minamino who made it 3-3 with seconds remaining of six added minutes.
The visitors crumbled under the pressure exerted in the second half having twice cruised into a two-goal lead as Jamie Vardy scored his ninth and 10th goals in 14 appearances against the under-strength Reds.
Alex Oxlade-Chamberlain briefly made it 2-1 before a brilliant James Maddison strike restored the Foxes' advantage.
However, the introduction of first-team reinforcements for the second half changed the dynamic as Jota and League Cup specialist Minamino, with his sixth in five appearances, forced a shoot-out.
Two years ago Liverpool fielded a youth team at this stage as the senior players were out in Qatar winning the Club World Cup and lost 5-0 at Aston Villa.
This time Reds manager Jurgen Klopp, facing five matches in 12 days, made 10 changes with three academy players in the team and another five on the bench.
Leicester, by contrast after 10 days off due to a Covid-enforced break, were virtually at full strength with Vardy returning to partner Patson Daka in a front two with Maddison at the tip of the midfield diamond.
But for all their clinical finishing the Foxes’ advantage was as much down to the hosts being their own worst enemies as for all three first-half goals Liverpool conceded they gave the ball away.
Considering the rotation and personnel that may not be surprising but it was the last thing they needed with such a patched-up side.
Joe Gomez set the tone in only the fifth minute when his loss of possession saw Daka counter-attack and force a save out of Kelleher.
Liverpool were not so fortunate with their next concession of possession, as when Kostas Tsimikas turned a blind pass inside the visitors seized the opportunity to cut through the centre of defence with Kelleher getting a hand to Vardy’s shot but unable to keep it out.
Four minutes later the former England hitman had doubled his tally as Neco Williams, a full-back playing as a right winger, lost the ball high up the pitch and Daka exposed 19-year-old Billy Koumetio down the left before crossing for Vardy to sidefoot home.
At that point it seemed Liverpool were set to be routed, so disjointed was their play, but Oxlade-Chamberlain’s goal changed the momentum and for a 15-minute spell it was Leicester who had a wobble.
Tsimikas’ long cross was knocked back by Williams for Roberto Firmino to bring down before laying off to allow the midfielder to drill home.
The next goal in a wild half looked like being decisive and it went to Leicester as this time young right-back Conor Bradley misplaced a pass and was cruelly punished by a dipping Maddison 25-yarder which Kelleher should have dealt with better.
Vardy should have claimed his hat-trick after a miscontrol by Gomez put him clean through and he beat the goalkeeper but not the post.
Klopp replaced his three academy players with considerable first-team experience in the shape of James Milner, Jota and Ibrahima Konate – quickly followed by Naby Keita – in an attempt to bring some control to the second half.
That answered the misconceptions about Klopp devaluing the League Cup but it was Leicester who were first to threaten, however, with Kiernan Dewsbury-Hall forcing a low save from Kelleher.
But when Jota fired home in the 68th minute the tie sprang to life again, with the Liverpool manager doing his best to whip up the crowd as Leicester started to crumble.
Only a brilliant recovery tackle from Wilfred Ndidi denied what looked a certain goal for Firmino while Kasper Schmeichel managed to parry Jota’s header after he dived into Keita’s long-range drive, and it looked as though the Foxes would hold on.
But one last effort saw Milner lump a ball into the area and Minamino fire home to set up a penalty shoot-out and ultimately an 18th League Cup semi-final – where they will play Arsenal – having won the competition eight times previously but not since 2012.