Defence is Klopp's biggest Achilles heel
Klopp will never achieve consistency and success without a solid backline
Stunned into silence, the 3,000-odd travelling fans could barely believe the familiarity of the sinking feeling.
They had just witnessed Liverpool throw away a 2-0 lead at St Mary's Stadium with a bout of pathetic defending in the second half, as Southampton hit back with three goals to win 3-2.
Painful memories came flooding back.
In 2014, they witnessed something similar, when the title-chasing Reds stumbled all over themselves in their own penalty box to lose a 3-0 advantage over Crystal Palace.
After a defensive display this farcical, Liverpool looked set to wield the axe at the end of that campaign.
But, astonishingly, the goalkeeper - Simon Mignolet - and three of the four defenders - Mamadou Sakho, Martin Skrtel and Jon Flanagan - from that match survived, and played in Sunday's match against the Saints.
If two years aren't enough time to solve a problem as fundamental as defending, then what does it say about Liverpool?
Not very flattering, to say the very least. An overhaul is long overdue.
Manager Juergen Klopp might have injected some optimism into the club since his arrival last October, but he can forget about leading the Reds back to their glory days with a defensive foundation this brittle.
Without a solid base, consistency is impossible.
It is why Liverpool can do the league double over Man City and still lose to Crystal Palace and Newcastle.
Premiership leaders Leicester City are propelled by twin terrors Jamie Vardy and Riyad Mahrez, but they are crucially supported by a reliable central pairing of Robert Huth and Wes Morgan, and goalkeeper Kasper Schmeichel.
Tottenham Hotspur's title tilt is founded on the rock-solid partnership of Toby Alderweireld and Jan Vertonghen, with the young Kevin Wimmer proving adequate cover for the injured Vertonghen in recent weeks, while custodian Hugo Lloris has been a driving force as well.
Even the enterprising Borussia Dortmund side that blossomed under Klopp benefited hugely from the unshakable Mats Hummels and Neven Subotic in the heart of the backline.
If Klopp is serious about rebuilding Liverpool, then he must be ruthless this summer.
Only a handful have impressed.
Fullback Nathaniel Clyne stands out with his consistency and reliability. Flanagan and Joe Gomez have the combination of youth and potential on their side, and Dejan Lovren has shown a marked improvement in recent matches following a atrocious start to his Anfield career.
The majority of the rest, though, has to go.
The likes of Mignolet, Skrtel, Sakho and Alberto Moreno - players who get regular playing time - are accidents waiting to happen.
Deadwood such as Adam Bogdan, Jose Enrique and Tiago Ilori have to make way for replacements.
On the bright side, Klopp is already working towards next season.
The highly-rated 24-year-old centre back Joel Matip, who will arrive from Schalke in the summer, is a free-transfer signing regarded as something of a coup.
The club have also approached Hoffenheim over the availability of Germany Under-21 defender Niklas Sule, while the names of Cologne's Jonas Hector and Paris Saint-Germain's Presnel Kimpembe have been linked with the Reds.
It is clear changes are needed, just like it was two years ago.
But if Klopp continues to deceive himself and think that this squad are good enough, then expect the Reds deserve to be stuck at where they are now - mediocrity.
RELEASE THESE REDS
Too error-prone and inconsistent for a player in a crucial position, although he fared well on Sunday. Liverpool must be prepared to ship the goalkeeper out even though he just recently signed a contract extension.
A loyal servant who looked horribly off the pace against Southampton after coming on as a half-time substitute. His numbers made for awful reading: 3 goals conceded, 1 penalty given away, 0 tackles won, 0 blocks, 0 interceptions.
Always seems nervous on the ball when opponents close down on him, and his lack of confidence can spread to the rest of the team like a plague.
PHOTOS: ACTION IMAGES, AFP, REUTERS
Injured for the Saints clash but he probably couldn’t have done much to prevent the loss. A threat going forward, but a terrible mess at the back.
There are 27 points still to play for. We can get all of them, there’s a chance. We don’t have to dream of things like this we have to play football and win games.
— Liverpool manager Juergen Klopp
BY THE NUMBERS
Southampton failed to muster a single shot on target in the first half against Liverpool.
Liverpool have never lost a game in which they were leading by two or more goals at half-time in their Premier League history until Sunday night.
Striker Sadio Mane has scored three of four Southampton goals against Liverpool this season.
Liverpool have dropped 15 points from leading positions this season, a Premier League high.
Klopp refuses to give up hope
Juergen Klopp refused to write off Liverpool's hopes of forcing their way into the top four despite squandering a two-goal lead at Southampton on Sunday.
Liverpool's 3-2 defeat meant they were unable to take advantage of Manchester City's home loss to Manchester United and move to within four points of Manuel Pellegrini's side who lie fourth having played a game more.
But Klopp insists that with nine games remaining, his side can still challenge, although he conceded they cannot afford a repeat of their second-half performance at St Mary's Stadium.
"There are 27 points still to play for," said the Liverpool manager.
"We can get all of them, there's a chance. We don't have to dream of things like this we have to play football and win games.
"If we played like the first half, we can win games. If we play like we did in the second half, it will be more difficult."
Klopp was left stunned after his side had apparently been in control at half-time after goals from Philippe Coutinho and Daniel Sturridge.
Southampton recovered to take the points with Sadio Mane scoring twice, the second an 86th-minute winner two minutes after Graziano Pelle had equalised.
"I'm not that good a loser so I don't feel brilliant at this moment, but this is football," said Klopp.
"We could have done better. I'm not angry, I'm frustrated of course because we got nothing. We played well in the first half and not in the second half, so for me that sounds like a draw, but we got nothing."
Klopp also played down what seemed like a heated discussion with Christian Benteke after the match.
The Belgium striker came on for 20 minutes, but didn't do his ability justice - shooting wide when one-on-one.
The Reds boss claimed that he wasn't angry at Benteke for that miss, playing the altercation down as a minor issue.
"I didn't say, 'Why did you not use the chance?'. No, no, no," Klopp told the BBC after the game.
"Sometimes we have to talk with players. That's my job. They're going with their national teams and I don't want to make phone calls so I just had a few words - that's okay. Nothing else."
Klopp also suggested he would sell Coutinho if he wanted to leave.
The 23-year-old Brazilian has been linked with Barcelona in the past while former Reds defender Jamie Carragher reckoned he could be worth between £50 million ($98m) and £60m.
Klopp insists that he would not keep a player against their wishes.
"Everything is okay at the moment, but nobody in the world - maybe only Lionel Messi - is unsellable," he said.
"If a player comes to me and says he doesn't feel comfortable and wants to leave because of our style of play or because he can make more money elsewhere, then you always have to start thinking.
"Coutinho, (Roberto) Firmino, so many players are very special. But, if a player wants to go to another club, then I'd always be open to it because I don't want to have a player in my squad who doesn't want to be in the squad." - Wire Services.
What the papers say
"Slick and polished in the first period, Liverpool were weak and confused after the break. (Sadio) Mane, who came off the bench at the interval, ran amok, while the imperious Graziano Pelle pounded the hapless Martin Skrtel and Mamadou Sakho into the ground."
- Daily Mail's Dominic King
"That defence never looked comfortable and will need to be strengthened if this team are to achieve sustainable progress. Dejan Lovren's improved performances had been one of the features of Liverpool's strong form but, on his return to the club where he began his (EPL) career, the Croat fell back into the haplessness of his early Liverpool days."
- The Guardian's Paul Doyle
"Juergen Klopp's introduction at the break of Martin Skrtel in favour of former Saint Dejan Lovren, who had been booked, was less successful, as Graziano Pelle dominated the Slovakian defender in the air and on the ground throughout the second half."
- The Independent's Nick Szczepanik
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