Liverpool overcame a valiant performance by Villarreal to book a third Champions League final in five seasons with a 3-2 victory at El Madrigal to complete a 5-2 aggregate win on Tuesday night
The six-time European champions saw their first-leg advantage extinguished in the first half as Boulaye Dia's third-minute opener was added to by Francis Coquelin, who outjumped Trent Alexander-Arnold to float a header into the top corner (41)
But Fabinho restored Liverpool's advantage in the tie when his near-post shot flashed through Geronimo Rulli (62)
 It turned the tide as the inspired substitute Luis Diaz restored the visitors' two-goal cushion from Alexander-Arnold's cross (67)
It was a very dominant second-half display from Jurgen Klopp's side, who capitalised on further dubious goalkeeping as Sadio Mane nipped in front of the roaming Rulli, rode the challenge of Juan Foyth to stroke into an unguarded net (74)
There was still time for Etienne Capoue to be sent off in the final five minutes following a second bookable offence on Curtis Jones as Liverpool march onto the Paris showpiece in 25 days' time, where an unprecedented quadruple might await
This was the epitome of a game of two halves
 It will be viewed as a missed opportunity in Spain for Villarreal after an opening 45 minutes in which Unai Emery was true to his word and Liverpool duly suffered
 The hosts embarked on a walk of honour at the final whistle with the city proud of a team dwarfed by the resources of their opponents
"We never make these Champions League semi-finals easy for ourselves," Alexander-Arnold told
 "Thinking back to Roma away and Barcelona at home and now here
 It was very difficult and they played very well in the first half
 But we regrouped at half-time and did what we needed to do
"For all their struggles in this enthralling second leg, Klopp's side - in the midst of a defining month in their season and indeed their history - are potentially just 90 minutes away from a seventh European Cup
The Estadio de la Ceramica had been battered by torrential rain throughout Tuesday, and the aptly named Yellow Submarine showed early signs of derailing Liverpool's quest for the greatest of achievements
The conditions proved a leveller as the hosts were given plenty of encouragement by halving the deficit
Pervis Estupinan was afforded too much time by Naby Keita to cross from the left, and after Capoue had ghosted around the back of Andrew Robertson, Virgil van Dijk was caught flat-footed as Dia pounced to tuck home the former Tottenham midfielder's miscue for his first Champions League goal
On a night of fine margins, Liverpool needed to look after the ball better but a slack header by Keita enabled Gerard Moreno to feed Giovani Lo Celso only for the Argentine to run into Alisson, who got the ball first with referee Danny Makkelie waving away penalty claims
It would only prove a short reprieve as Villarreal would level the tie before the interval as Pau Torres' long diagonal was collected by Capoue and despite the attentions of Robertson, a cute turn and cross found Coquelin rising above Alexander-Arnold at the far post to glance home a sensational second
Liverpool needed to come out fighting in the second period having had three touches in the Villarreal penalty area for their lowest first-half total in all competitions this season
Swapping game-changer Diaz for Diogo Jota for the start of the second half made an immediate improvement, allowing Mane to play centrally, where he has done well recently
Alexander-Arnold very nearly re-established Liverpool's advantage when his strike from distance following a quick free-kick looped off Coquelin and clipped the crossbar
Two minutes later, Alexander-Arnold was again involved as he found Mane in space down the right but Diaz was unable to connect cleanly with a scissor-kick from the ensuing cross
Villarreal looked like they had expended all their energy and with Liverpool's next attack, they nudged ahead to land a huge psychological blow
 Capoue committed himself to challenging Salah, who observed the space in behind to feed Fabinho
 The error-prone Rulli anticipated a cross to create space at his near post but the Brazilian would blast through the goalkeeper's legs
Liverpool fans could finally smile and after Diaz had seen a shot deflect just wide, the Colombian restored his side's two-goal lead in the tie as his downward header from Alexander-Arnold's cross again went through the legs of Rulli
It was now one-way traffic and after another poor error of judgement from Rulli, Mane kept his composure to end any hopes of a second dramatic comeback as he latched onto a long ball to slide home his 15th Champions League knockout goal
The win stretches Liverpool's unbeaten run to 13 games in all competitions
 A 43rd success of the season extends a club record for most victories in a campaign
 Liverpool look a team of destiny even when not at their best - is there anyone who can stop them?"[It was] hard work
 The first half we should forget as soon as possible
 Our aggression on the ball wasn't good enough
 The early goal doesn't help us and helps them massively so we had to dig deep
"We had to be very mature and obviously second half we played outstanding
 On the ball, without the ball, winning the ball back as quickly as possible and then it's going to be difficult for them to keep up with the press and the runs
"It was a well deserved win based on the second half
 First half, of course, it could've been different
"Asked what Klopp said at half-time, he said: "Play football
 Play the Liverpool way, how we've basically played all season
"Get on the ball, have a lot of movements behind their high line
 With the speed we have, we had to mix it up
 But also, you have to show how much you really want to go to the final, that's how it starts
 Second half we dominated and played so well
""It feels like the first final in 20 years! It's outstanding
 We obviously made it pretty tricky for ourselves but we knew before that these kind of things can happen
 Life is always about how you can react when things don't go your way
"Getting the first goal after two or three minutes, that's the opposite of what you want
 Respect to Villarreal
 Stadium, team, coach
 Unbelievable
 They put us under pressure man-to-man all over the pitch and we didn't play football at all
"I told the boys, 'Yes, they have momentum, but they don't own it
 With one situation we can get it back
 We have to play in the right spaces and we have to force ourselves to start playing football
'"All of a sudden, we broke the lines and found Naby and Trent in the half-spaces and we were in the game, we scored goals and we made it happen
"It is a good time to be a Liverpool fan, who can look forward to two more finals this season
 Indeed, Klopp has guided them into an eighth final during his time as manager and they are just six games away now from an historic quadruple
Liverpool came here to complete the job, show professionalism and to finish what they started a week ago in the face of a crackling atmosphere - but they showed signs of frailty in the opening 45 minutes
Experience would eventually tell, aided and abetted by a distinctly ordinary goalkeeping performance from the hosts' Geronimo Rulli
Liverpool had been in this position twice before under Klopp, progressing on both occasions before losing the 2018 final to Real Madrid and winning a sixth European Cup against Tottenham the following year
Only one team has ever overturned a two-goal deficit from a Champions League semi-final - Klopp's Liverpool against Barcelona that season
 Their know-how, particularly in 2019, certainly helped here in spite of Emery's own very proud knockout history in European competition
He was the PSG manager on the receiving end of Barcelona's infamous 'Remontada' in 2017 - and was described as the "king of the cups" by Klopp - but this proved a step too far even for him to mastermind his own turnaround for a team currently seventh in La Liga
Ending May with four trophies in the cabinet is becoming an increasing possibility for Liverpool
 The Carabao Cup was secured in February, and they can also look forward to an FA Cup final in just under a fortnight's time; underlying all of that is another epic title race which is set to go right down to the wire with Manchester City only one point ahead with four matches
The relentless pursuit of a quadruple - and a seventh European Cup - rolls on
Liverpool's hectic schedule continues as they host Tottenham in the Premier League on Saturday at 7
45pm knowing they cannot afford to slip up if they are to catch Manchester City