Few who have endured the flipside to the Merseysiders' campaign to date will be concurring just yet, but the significance of Rafael Benítez's achievement should not be underestimated. Three years ago Bayer Leverkusen humbled Liverpool in the Rhineland and, while the Germans boasted a far better side then, this was an annihilation few envisaged. The visiting fans crowed "We've only won it four times"; slowly but surely, belief is swelling that they could yet pluck an improbable fifth European Cup from a bizarre mishmash of a season.
"The other teams in the competition will watch our game tonight and will start to say: 'Be careful, they won't be easy opponents,'" said Benítez. "As a team, this display will have given us much more confident.
"We'll watch the draw for the quarter-finals with interest and see what we can achieve in this competition, but we're not thinking about winning the Champions League yet. We're only looking to the next game."
For the moment it should be enough to revel in the knowledge that Liverpool have endured longer than Arsenal and Manchester United in this competition. Leverkusen's previously imposing form in this arena had suggested this would prove an awkward encounter, though it proved anything but daunting. By the interval Liverpool's progress was assured, their aggregate advantage stretched to four goals and the Germans' most prolific scorer, Dimitar Berbatov, nursing a rib injury and replaced.
Yet it was the shambles that passed as the hosts' makeshift defence which proved decisive, with the visitors revelling in their discomfort. Luis García's brace midway through the first period effectively propelled the Merseysiders through, but it was Steven Gerrard's presence which inspired. The captain missed the first leg of this tie through suspension and spent the opening exchanges here misplacing passes at an alarming rate, his form apparently still anchored by the wretched memory of the Carling Cup final. But once he shrugged himself from his malaise, Liverpool were untouchable.
It was the England midfielder's exchange of passes with Milan Baros which forced Bayer back as the half-hour approached, Diego Placente blocking the Czech's charge for Gerrard to batter at goal. Jorg Butt did well to turn that shot aside but the home side were pinned back from the resultant corner, Gerrard given time to skim a cross from the right which García, eluding the dawdling Placente, flicked eagerly home from the edge of the six-yard box.
Leverkusen were grounded, their misery compounded within five minutes as Gerrard's corner was nodded down by Igor Biscan for García, from point-blank range, to prod his eighth goal of the season into the empty net. The Spaniard might have plundered a first-half hat-trick had Butt not tipped aside another belted attempt leaving Placente to take out his frustrations on Baros off the ball, the elbow flung at the Czech going unnoticed by the officials.
The Argentinian's anguish - if not his conduct - was understandable. Bayer had revelled in swashbuckling victories over Real Madrid, Roma and Dynamo Kiev in this competition's group stage before Christmas and dispatched Bayern Munich 4-1 in a Bundesliga game here this season. Yet the storm they had hoped to whip up had fizzled disastrously, checked by air-kicks from Landon Donovan and Franca in presentable positions before the break.
When Jacek Krzynowek did finally pierce the visitors, lashing home from close range with two minutes remaining, there was little cause to celebrate. By then the visitors had added a third, Baros trundling easily into space to spear beyond Butt. That they played You'll Never Walk Alone on the final whistle seemed strangely appropriate, so accommodating had the hosts been all night.
There will be concern at the uncertainty which occasionally flared in the visitors' rearguard, the substitute Andrej Voronin and Franca both skying efforts from Daniel Bierofka's centres. Better teams than Bayer will punish Liverpool, and seven of them await in next week's draw. But, for now, prospects appear rosy.
Benítez spent Tuesday night mixing with his people, the Spaniard coaxed to Jameson's Irish bar in Cologne by a group of Liverpool supporters to watch Manchester United slip out of this competition on the big screen. The manager entered the pub to a stunned chorus of "Rafa get the ales in"; after his side's display here, he may never have to buy a drink again.