Jamie Carragher says Liverpool will struggle to win the league this season if they do not sign a new centre back.
Liverpool surprisingly lost 1-0 to Southampton on Monday which has blown the Premier League title race wide open with Manchester United level on 33 points.
Central defence has been a problem for Liverpool this season with Fabinho and Jordan Henderson at times being asked to drop back because of injuries to Joe Gomez, Joel Matip and Virgil van Dijk.
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Ex-Liverpool defender Carragher believes the Premier League champions need to sign another centre half if they are to retain the title.
"I can't see Liverpool winning the league if they don't buy a centre-back," he told Sky Sports.
"I said that after the Everton game when (Virgil) van Dijk was injured but I think it's a really tough ask if they don't bring anyone in.
"The fact they played Jordan Henderson at centre-back is not going to do a lot for the two lads on the bench (Rhys Williams and Nathaniel Phillips) and their confidence if they have two midfielders playing there.
"Henderson is not a centre-back. He did well, but it's not his position."
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FOUR DEFENSIVE TARGETS LIVERPOOL COULD SIGN
With defensive injuries mounting, and their place as England's number one side under threat, will Liverpool make any signings in the January transfer window?
We take a look at potential options for Jurgen Klopp's team, including RB Leipzig defender Dayot Upamecano and Bayern Munich's David Alaba, who is out of contract next summer.
LIVERPOOL'S KEY TARGETS - INSIDE FOOTBALL
There has been talk that Klopp would need to enter the market for back-up. However, there are still no concrete plans to do so.
Ozan Kabak of German club Schalke is a realistic target but AC Milan are also tracking him and the Serie A leaders are in a good position to go and seal the deal if they decide he is the man to suit their needs at the back.
If Liverpool do sign a centre-back though, look out for Sporting Braga’s David Carmo and RB Salzburg’s Max Wober among the potential options they could pursue. Sven Botman from Lille is also emerging as an option.
Liverpool’s main focus right now is to convince Gigi Wijnaldum to sign a new deal. Klopp is desperate for him to stay and there are other figures at the club too who are stunned that he could be allowed to become a free agent.
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