The Reds have been heavily criticised for their poor performances at the back under Jurgen Klopp over the past month or so.
Liverpool have already conceded 12 times in seven games in the Premier League ahead of Manchester United’s visit at Anfield on Saturday afternoon.
The Merseyside outfit lost 5-0 to Premier League leaders Manchester City at the start of September to trigger a run of one win in seven games in all competitions.
Liverpool have also conceded seven goals in four games in the Champions League despite coming up against Sevilla and Spartak Moscow.
Worryingly for Liverpool supporters, only Manchester City have scored more goals than Manchester United in the Premier League this term ahead of this weekend’s north-west derby.
Former Chelsea striker Cole believes Liverpool need to sign a commanding defender to improve Klopp’s back four.
“They need leader on that pitch to say let’s protect that back four,” Cole told BBC Radio 5 Live.
“They need help. It’s all about communication.”
Liverpool signed AS Roma winger Mohamed Salah, Chelsea teenager Dominic Solange, Hull City defender Andy Robertson and Arsenal midfielder Alex Oxlade-Chamberlain in the summer transfer window.
The Reds have also reached a £48m agreement with Bundesliga side RB Leipzig to sign Naby Keita next summer.
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