Arsenal twice squandered the lead as they were dumped out of the EFL Cup by Liverpool on penalties after a remarkable 5-5 draw at Anfield.
Under-pressure Gunners boss Unai Emery needed a positive result to lift the gloom around Arsenal after they let slip a two-goal lead to draw 2-2 with Crystal Palace, but Jurgen Klopp's irrepressible young Reds prevailed.
Shkodran Mustafi's own goal and James Milner's penalty bookended a Lucas Torreira strike and Gabriel Martinelli's double in a first half characterised by defensive errors and gung-ho attacking.
Ainsley Maitland-Niles extended Arsenal's 3-2 interval lead before strikes from Alex Oxlade-Chamberlain and Divock Origi levelled the contest, only for Joe Willock to put Arsenal back in front with a wonderful solo effort 20 minutes from time.
But Origi penetrated Arsenal's porous defence again to take the game to penalties, and Dani Ceballos had his spot-kick saved as Liverpool clinched a place in the quarter-finals at the expense of their beleaguered visitors.
Mustafi inadvertently bundled the ball past Emiliano Martinez with his knee to put Liverpool ahead before Torreira appeared to come from an offside position when he side-footed home the equaliser.
Arsenal went ahead when a quick free-kick caused havoc in the Liverpool box, before Martinelli lashed his side's second high into the roof of the net. Teenage home debutant Neco Williams then gave possession away cheaply to allow Martinelli to score again.
Moments later, Brazilian forward Martinelli was judged to have fouled Harvey Elliott in the box and James Milner buried the ensuing penalty. But Milner's calamitous back-pass let Maitland-Niles steal in and - after Mesut Ozil kept the ball in play with a sensational drag-back - restore Arsenal's two-goal advantage.
Oxlade-Chamberlain unleashed a wickedly dipping shot that screamed over Martinez and into the net to make it 4-3 before Curtis Jones drove Liverpool forward and picked out Origi who found the net with a fortuitous drive.
The pick of the goals came from Willock who was allowed to run through Liverpool's midfield before curling an exquisite finish into the top corner from 25 yards.
But Arsenal's habit of letting leads slip struck again when Origi was left unmarked 12 yards from goal and he volleyed Williams' cross beyond Martinez to send the match to penalties.
Hector Bellerin, Matteo Guendouzi, Martinelli and Maitland-Niles held their nerve in the shoot-out but Kelleher saved from Ceballos to allow Jones to score the winner at the Kop end.
Klopp's focus is clear
A Liverpool team showing 11 changes from Sunday's 2-1 win over Tottenham told its own story: Klopp's priority is the Premier League, but his young charges showed their mettle.
Martinelli stakes his claim - again
A second EFL Cup start for Martinelli delivered a second brace in the competition from the 18-year-old forward who is showing the kind of promise that could see him regularly involved in the Premier League before long.
