Liverpool have once again been urged to temper their defensive frailties by signing a centre-back during the upcoming January transfer window.

No side has shipped more goals in the Premier League's top seven this term than the Reds despite goalkeepers Simon Mignolet and Loris Karius keeping eight clean sheets between them.

On seven occasions in all competitions Liverpool have conceded two or more goals in a single game, with Dejan Lovren, Ragnar Klavan and Joel Matip all struggling this season.

The showing sees them trail league leaders Manchester City by 18 points; out of the Carabao Cup after defeat to Leicester City and left them needing to beat Spartak Moscow in their final Champions League group game to qualify for the last 16.

And former City defender Richard Dunne has joined the growing list of fans and pundits to suggest that Liverpool must move to improve their defence when the transfer window reopens on 1 January.

"Liverpool need a centre-half. The ones they've got are the wrong ones," Dunne told Irish radio station Newstalk, according to The Sport Review. "They've not performed well. The centre-halves are a little bit mentally weak. They can be bullied. They can make the wrong decisions."

Dunne, formerly of Everton, Aston Villa and Queens Park Rangers, added: "They signed Keita for £50m or £60m. They are looking at another centre-forward. You look at it and say just go buy a centre-half."

Speaking last month, Dunne had suggested that Brighton and Hove Albion and Republic of Ireland defender Shane Duffy could represent a viable option given his success this season.

Duffy, 25, has started all of Brighton's Premier League games this season in their first campaign back in the top flight in 34 years, helping the club occupy a place in mid-table three points above the relegation zone after 18 matches.

But he was part of the back-four which shipped five when Liverpool visited the Amex in December, though that should not detract from his otherwise accomplished displays.

"His tackling is outstanding," Dunne told Newstalk, according to Sport Review. "His reading of the game is improving. There's no-one better when it comes to heading the ball in the air. His performances for Ireland and Brighton over the last two months, he is putting himself in the bracket where people are starting to notice him now.

"When you think of Liverpool and Arsenal are desperate for a centre-half, he is someone people are going to start talking about. Brighton are keeping clean sheets and in the top 10 in the league. He's one of their star performers. He is young enough to go to that level. He has so much room to grow."

Manager Jurgen Klopp has been typically coy over Liverpool's plans for the January market, though the German coach has ruled out Naby Keita - due to join from RB Leipzig in the summer - moving to Merseyside ahead of schedule.

"We think all the time about this," Klopp said, according to the club's official website when asked about possible new recruits..

"It's not only the January window, the summer window is coming as well, so we have to prepare for things like this with scouting and stuff like this. But [I have] nothing to say about them."

Jurgen Klopp
Klopp has again been urged to improve his defence. Getty Images