Liverpool have conceded 12 times already this season... so where is it going wrong and how can Jurgen Klopp stop his side leaking goals?

• e-mail

It was a moment symptomatic of just how suspect Liverpool's defence has been this season.

Newcastle United's Joselu, a decent striker but not one of huge repute, darted straight through the Reds' soft centre to take points off Jurgen Klopp's side at St James' Park.

Only Crystal Palace and West Ham have conceded more goals in the Premier League this season than this Liverpool side, who are supposed to have the highest of ambitions.

Jurgen Klopp watched on as his side squandered yet more points in the Premier League

Joselu secured a point for Newcastle against Liverpool at St James' Park on Sunday afternoon

Instead, their defence is leaving an otherwise potent side looking short of what is needed to challenge for honours.

Here, Sportsmail looks at where it's going wrong for the Reds — and how Klopp could try to fix it.

Why is their defending so bad?

Conceding 20 goals in the opening two months of the season shows the difficulties Liverpool have had so far, and their backline has been far from convincing.

It's a familiar scene. They haven't kept a clean sheet since beating Arsenal in August and, on Sunday, their hopes of ending that unfortunate run were undone by one of the season's more embarrassing concessions.

Liverpool look particularly vulnerable on the counter-attack when their central defenders switch off, losing concentration and inviting pressure for teams who will move the ball quickly into their half.

On the left, Alberto Moreno is perhaps the poster-boy for it all: a player who has looked frail in defence, excluded by Klopp in favour of a midfielder for much of last season, but now back in a key role and with more focus on attacking than going the other way.

Joe Gomez, who has been at right back of late, is improving but not at the level a top side needs yet. Andrew Robertson, a summer arrival from Hull City, is gradually being eased into action.

Left back Alberto Moreno is perhaps the poster-boy for all of Liverpool's defensive frailties

And why has Klopp not sorted it?

This is perhaps the most difficult question to answer. Klopp courted Southampton's Virgil van Dijk this summer in a failed pursuit but then deemed other targets to not be worth following up on.

The manager's answer over why? 'We watched all of them 500 million times,' Klopp said last month. 'I had to make a decision and the decision was our boys are not worse than them.'

Klopp signed Joel Matip in a free transfer from Schalke last summer before purchasing Ragnar Klavan in a £5million deal from Mainz — but his investment in the centre of defence has been notably lacking otherwise.

For now, the German seems to believe that there were not better options than the ones he already has on the market this summer.

And that is difficult for anyone who has watched Liverpool's defence this season to believe.

Virgil van Dijk was a target throughout the summer but he is now back in the Southampton side

Who are the main culprits?

On the pitch, individual errors have been costly for Liverpool, most notably in the centre of defence.

Matip's lack of attention cost them the Joselu goal on Sunday and although he did well to get back and make a late challenge, the end result was the Spanish striker finding the net in fortunate circumstances.

Dejan Lovren, who says he is taking painkillers to get through each game, has also often been found out with alarming regularity and Klavan is not a regularly viable replacement either.

Liverpool players applaud the travelling support after Sunday's draw at Newcastle

Klopp has also been chopping and changing his back four and rotating between Simon Mignolet and Loris Karius in goal, moves that hardly inspire confidence or comfort.

Off the field, the much-maligned Anfield transfer committee and Klopp should shoulder the blame for a lack of serious recruitment.

Liverpool's Mike Gordon, Michael Edwards, Dave Fallows and Barry Hunter all work with the boss to identify, negotiate and purchase targets and that simply did not work out this summer — again.

Dejan Lovren admits he is taking painkillers to get through every game due to injuries

What alternatives are there?

Klopp appears to have indicated the defensive issues come from the way Liverpool are set up to attack — but don't expect him to change his ways in that department just yet.

There aren't many other options in the squad, either. James Milner could be moved back into defence to improve the solidity of the backline but that is far from ideal and the same goes for Alex Oxlade-Chamberlain. Trent Alexander-Arnold has impressed in bits and pieces — but relying on an 18-year-old full back to transform this mess would be absurd.

If Klopp believes the quality level he wants out was not on the market in the summer, he might find it difficult in January too, when player availability is more restricted. 

James Milner has been utilised in the defence previously and could be moved back again

So who have Liverpool got working with the defenders?

'Usually, I'm a really good defensive coach,' Klopp said when quizzed on Liverpool's issues at the back last month. But all too often his side have been undone at set pieces or in the face of a direct attacking threat spooking their backline into mistakes.

The former Borussia Dortmund boss is supported chiefly in his role by first-team assistants Zeljko Buvac, Peter Krawietz and Pepijn Lijnders.

Krawietz, a former video analyst from when Klopp was a player at Mainz, is the tactical string-puller at Anfield and is said to provide constant suggestions, amendments and advice for improvement.

Liverpool look a dream going forward but this team have not been good enough in that department when it comes to their defending.

On the transfer committee, Gordon and Edwards deal with the role of identifying targets and seemingly could not provide Klopp and Co with options they were happy with in the summer.

Klopp says he is 'usually a very good defensive coach', but his side have conceded plenty

And is there any chance of signing Van Dijk? Or any other options?

It seems unlikely that Van Dijk, now back in the Southampton side, will move in January but another summer chase could be on the cards.

The winter window looks a difficult time to shop at the level Klopp is looking for, so it could be a long wait until Liverpool see significant improvements at the back.

Ryan Sessegnon has been linked with the club regularly but is more of a long-term-focused option than an immediate fix. New targets are needed. 

Fulham's Ryan Sessegnon is regularly linked with the Reds, but he is more of a long-term target

Has Klopp had this problem before?

Somewhat worryingly, there were clear defensive tactical limitations for Klopp as his Dortmund dynasty fell apart in its final season in 2015.

His defence became prone to individual errors under pressure at times and they failed to find a way to adapt to improve on the issue.

But that should not be used as a stick to beat Klopp significantly: winning two Bundesliga titles in Germany ahead of Bayern Munich does not come without a solid defensive core. With the right personnel, he has shown an ability to find solidity in this department. 

Klopp's Dortmund dynasty fell apart in its final season in 2015 before he moved to Liverpool

How does he fix it from here?

All is not lost for Liverpool: a reminder needs to be made that they have lost just once this season even with their defensive problems.

But Klopp certainly needs to sort something out if they are to be serious challengers for major titles, most notably in the Premier League.

For now, perhaps something of their swashbuckling style needs to be sacrificed to improve a defence that looks in serious trouble when its full backs are pushed up and the midfielders offer little to help out the centre backs when faced with pace and direct play.

Beyond that, the need for recruitment is obvious. Whether it comes from splashing the cash on Van Dijk or elsewhere, Klopp needs more quality to make Liverpool contenders.

Philippe Coutinho is firing in goals, but some of their attacking prowess should be sacrificed