The locals had unfurled a banner prior to kick-off last night upon which three Benfiquistas, masked and mischievous, were portrayed scurrying away through the Shankly Gates with the European Cup. True to miserable form, Liverpool returned to Merseyside in the small hours sensing they had been mugged by the Portuguese, with their grip on this trophy in danger of slipping.
For 84 minutes here, the visitors strutted around the stadium with their dominance rarely challenged if lacking the bite to dismiss their flustered hosts. Then Dietmar Hamann tripped Giorgios Karagounis, and from Petit's free-kick the Brazilian Luisao rose to flick a header beyond Jose Reina and into the corner. Liverpool, so strong defensively and controlled in possession, had been undermined at the last.
Not since November 2004 had Rafael Benitez's team been beaten in this competition. Back then they were sluggish and deservedly dismissed by AS Monaco. In Lisbon last night, their slick performance should have assured progress to the quarter-finals, only for familiar failings in front of goal to flare again. Three times Liverpool have collided with the Portuguese in this competition and, on each occasion, they have landed in the final. Suddenly, that record appears in jeopardy.
Steven Gerrard's presence only among the substitutes, the midfielder rested with a dead leg sustained against Manchester United, had prompted a murmuring of concern among the travelling support. English sides, from Manchester United to the national team, have come unstuck here since this stadium was re-built and, when absent, the captain's urgency and bite are always missed.
The frustration was that had he been available the visitors might have transformed their domination into first-half reward to forge ahead in the tie, though they must still have drawn encouragement from their poise.
Even with Luis Garcia booked after 29 seconds for flooring Leo, and Mohamed Sissoko retired with a head wound just after the half-hour, the Merseysiders wrested control and were immaculate in possession, Garcia's occasional over-elaboration aside.
What sporadic threat Benfica posed was stifled, and Simao Sabrosa's free-kick in stoppage time whistled high and wide to sum up their inadequacy.
The hosts have been shoddy domestically recently and Ronald Koeman entered this contest a manager under pressure, with three of the Portuguese champions' last four matches lost and an ominous contest against the leaders Porto looming at the weekend. Liverpool played on their fragile confidence, pinging the ball around with ease.
Robbie Fowler, making his first appearance in this competition since November 2001 and a chastening 3-1 defeat at Anfield to Barcelona, was all clever flicks and tricks.
His back-heel from Xabi Alonso's scuttling free-kick prompted panic in the home ranks, the loose ball eventually hacked clear as Sami Hyypia threatened to convert.
Fowler had returned to the European champions last month with a brief to score rather than create chances, though he watched in anguish as Garcia shanked a half-volley wide from Harry Kewell's centre immediately upon the restart.
The Spaniard's dawdling, having collected Alonso's punted free-kick before twisting away from Alcides, summed up his infuriating inconsistencies, another opportunity wasted.
Chances so presentable are not falling for Fowler at the moment and he must have gnashed his teeth at the sight of Fernando Morientes leaping to flick John Arne Riise's throw-in over the bar, having gleaned tantalising space in the area.
By then, Fowler had departed for the bench, with Djibril Cisse's eager running introduced to expose Benfica's heightened desperation. It said much for their toils that Petit carved their most coherent sight of goal up to then with a shot from the halfway line which Jose Reina claimed with no little disdain.
Yet, from their mishmash of a display, Benfica still plucked the decisive free-kick in the closing stages which had the Spanish goalkeeper cursing his way home.
BENFICA: Moretto, Alcides, Luisao, Anderson, Leo (Ricardo Rocha 87), Robert (Nelson 76), Petit, Beto (Karagounis 58), Manuel, Simao, Nuno Gomes. Subs not used: Quim, Mantorras, Karyaka, Marcel. Booked: Beto. Goal: Luisao 84.
LIVERPOOL: Reina, Finnan, Carragher, Hyypia, Riise, Luis Garcia, Sissoko (Hamann 35), Alonso, Kewell, Morientes (Gerrard 78), Fowler (Cisse 65). Subs not used: Dudek, Crouch, Traore, Warnock. Booked: Luis Garcia, Hamann.
Referee: K Plautz (Austria).