A fortnight after an added-time winner put Liverpool into the last four of the Europa League, a similar fate befell them as they lost their semi-final first leg 1-0 in Villarreal.
The match appeared to be heading for a stalemate until substitute Adrian Lopez poked home two minutes into injury time.
It was less dramatic than Dejan Lovren's header against Borussia Dortmund two weeks previously - Jurgen Klopp's side still have the home leg to come - but frustrating nonetheless as they had appeared to have ground out a draw.
Going to the El Madrigal, where the hosts have now won all seven Europa League ties this season and are unbeaten in the competition since matchday one on September 17, was always going to be tough - but the Reds seemed to have done the hard work until a momentary lapse in concentration cost them.
Daniel Sturridge was on the bench again for Liverpool - a pattern repeated over four European matches now - despite his four goals in the last five games. Roberto Firmino was given the role as a nominal centre-forward.
While the Brazil international did a lot of the hard yards, pressing from the front as per his manager's instructions, he could offer neither the pace nor precision Sturridge has.
Klopp had urged his players not to waste that dramatic win over his former side two weeks ago and Joe Allen, on his first European start since November 26 and only his fourth in the competition this season, almost got them off to a flier.
Arriving into the penalty area at speed in the fifth minute he could only direct Adam Lallana's cross straight at Sergio Assenjo when a shot a yard either side of goalkeeper would have produced the breakthrough.
Without the focal point of Divock Origi, who injured ankle ligaments a week ago in the Merseyside derby but fortunately does not require surgery and could make a return before the end of the season, Liverpool were aimless in the final third.
Too often crosses were swung in at no one in particular, giving centre-backs Eric Bailly and Victor Ruiz an easy ride.
As a result Villarreal had the better chances with former Tottenham striker Roberto Soldado off-target with two shots at either end of the half, while Simon Mignolet got down well to parry Tomas Pina's low effort.
Villarreal right-back Mario Gaspar also had efforts snuffed out by Kolo Toure, continuing in central defence with Mamadou Sakho now officially suspended by UEFA for a failed drugs test - and Lovren.
The ineffectual Philippe Coutinho - reportedly being watched by Barcelona scouts - was replaced by winger Jordon Ibe at the break after feeling unwell but within 40 seconds of the restart Cedric Bakambu headed against the post from Jonathan dos Santos' corner.
Firmino, having kept himself onside, responded midway through the half with a shot which Asenjo tipped onto the upright - but that was as close as the visitors came.
Mignolet came to their rescue three minutes from time when Bakambu seized on Ibe's mistake while charging full-back Alberto Moreno ignored the unmarked winger from a quick counter-attack and instead fired into the side-netting.
But in added time substitute Lopez slid home after Denis Suarez had outpaced Toure.
TWEET OF THE MATCH
Stan Collymore @StanCollymore: "#LFC had them and let them off the hook. Manager deserves criticism tonight for subs or lack of."
PLAYER RATINGS
Liverpool
Simon Mignolet: 7/10
Nathaniel Clyne: 6
Kolo Toure: 6
Dejan Lovren: 6
Alberto Moreno: 6
James Milner: 5
Lucas Leiva: 7
Joe Allen: 7
Adam Lallana: 5
Philippe Coutinho: 5
Roberto Firmino: 5
Substitutes
Jordon Ibe (on for Coutinho, 46): 4
Christian Benteke (on for Firmino, 90): 6
STAR MAN
Joe Allen. The Wales midfielder does not get many starts under Jurgen Klopp and appears to be playing for his future but he was a bright spot all over the pitch and did not allow his early miss to affect him.
MOMENT OF THE MATCH
Allen's fifth-minute miss. An early away goal beckoned but the midfielder could only direct his shot straight at Sergio Asenjo.
VIEW FROM THE BENCH
Klopp made a big call in preferring Roberto Firmino to Daniel Sturridge and it did not pay off.
The Reds boss had one short, explosive row with opposite number Marcelino but was otherwise relatively undemonstrative. Sending on Christian Benteke in the 90th minute after a month of inactivity seemed pointless.
MOAN OF THE MATCH
Liverpool's lack of quality in the final third - considering how many ball players they have in the line-up - and lack of imagination in throwing crosses into the box in the first half with no one of any height to threaten.
WHO'S UP NEXT?
Swansea v Liverpool, Barclays Premier League (Sunday, May 1)
Valencia v Villarreal, Primera Division (Sunday, May 1)
Klopp was visibly frustrated with the late goal in what he says was Liverpool's only mistake of the match and believes his side will be tough opponents when they host the return leg next week.
He told BT Sport Europe: "We were not happy with the goal we conceded in the last second or something.
"But it's only the first leg....we had not the luck today. Nothing happened so it's one-nil, they have to come to Anfield now and they know how strong we are.
"To be honest I thought we would have more problems here. We defended really good, we had our moments to play football. They couldn't defend us - this race is not over.
"They played this one chip-ball in the back of Kolo...but that was the only big mistake we made in the game. Okay they scored with it, that's how it is you have to accept it. It's no problem really, no problem.
"Ninety minutes played, 95, we could play 97 at Anfield and that's a different game there."
Goalkeeper Mignolet took a more positive approach after the Reds more than held their own in Spain and is confident they can turn things around with their home support behind them.
He said: "I think we defended really well throughout the game. It's a tactical game against a Spanish team. We played a good game and they're hard to break down and they were looking for one or two chances and unfortunately it happened at the end.
"I think we played a good game and everybody saw the quality of Villarreal but we created our chances and we had some chances to score but that didn't happen - but still we have to play at home at Anfield and with our supporters behind us there's always magic in the air."
Toure said: "We know we can do it, we just need to believe.
"This game is done now. We just need to learn from the mistake we made and then try to do the same game we played against (Borussia) Dortmund."
Source: PA
