Sevilla 3 Liverpool 3
Maribor's added-time equaliser against Spartak Moscow opened the door not only for Liverpool to qualify with a match to spare but win the group outright but they did not so much as walk through as blow it off its hinges with a scintillating first half of football.
They then spent the next 45 minutes desperately trying to barricade the hole they left behind as the half-time introduction of Franco Vazquez sparked Sevilla into life.
It means Liverpool need a point at home to Spartak to now qualify but Sevilla could snatch top spot as they play already-eliminated Maribor.
Liverpool certainly cannot afford another Jeckyll and Hyde performance like this one.
The difference between the two halves was stark as just 90 seconds had passed when Georginio Wijnaldum flicked Philippe Coutinho's corner to the far post where Firmino stabbed home.
A stunned Sevilla side would have been level had Sergio Escudero not fired into the side-netting instead of crossing and then Loris Karius, goalkeeper for European games only, produced a brilliant fingertip tap to divert Nolito's shot onto the far post - from where it rolled back across goal before being cleared.
Liverpool heeded the warnings and stepped up a gear with Jordan Henderson putting Firmino through only for the Brazilian to disappoint with his finish allowing Sergio Rico to turn the shot behind.
The save proved academic as what followed was a virtually identical Coutinho corner, this time flicked on by Firmino for Mane at the far post.
On the half-hour Mane was sent flying down the left leaving defenders trailing in his wake and when his shot was parried Firmino tapped into an empty net, the easiness of the goal matched only by the Brazilian's cheekiness in converting while looking the other way.
The game seemed out of sight and the in-form Salah should have left no room for doubt just before the break when Coutinho reproduced an almost carbon-copy of the pass which led to the Egyptian's second goal against Southampton on Saturday only for the winger, who matched it with a similar run, lacking the finish this time.
Eighteen months ago Liverpool held a slender half-time lead in the Europa League final but capitulated to lose 3-1 and there was a sense of history repeating itself as Ben Yedder struck twice.
As in the European final in Basel Alberto Moreno, returning to his former club, was most culpable as he was responsible for both fouls allowing Ben Yedder to head in a near-post free-kick and then tripping the Sevilla striker to allow him to score a re-taken penalty.
The Spaniard was unceremoniously hauled off with Coutinho as James Milner, reprising last season's left-back role, and Emre Can were sent on to steady a rapidly-sinking ship only for Pizarro to nick a point at the death.