The Reds signed Loris Karius in a £4.7m deal from Mainz in the 2016 summer transfer window to supposedly replace Simon Mignolet.
However, the German goalkeeper struggled to usurp Mignolet as an automatic starter following some error-strewn performances.
The Belgium international has never convinced in the Liverpool FC goal under Brendan Rodgers and his successor Jurgen Klopp.
Mignolet started the season as number one but his performances led to Klopp’s decision to demote him to second choice.
Karius has impressed over the past couple of months to help Liverpool FC cement their top-four challenge and reach the Champions League last eight.
With Mignolet rumoured to be up for sale ahead of the summer transfer window, Liverpool FC will need to sign a goalkeeper to provide competition for Karius.
Former Reds defender Nicol believes Liverpool FC should look to sign a proven world-class goalkeeper to finally address the weak link in their team.
“Liverpool’s problems have been the defensive unit,” Nicol told ESPN FC. “The centre-half position and the goalkeeper.
“They’ve made a difference signing Van Dijk. Karius as good as the last few months has been, I am not ready to rely on him.
“Liverpool have to go out and get a number one.”
Liverpool FC finished in fourth place in the Premier League table last term and finished above Arsenal in the top four.
The Merseyside outfit signed Netherlands international Virgil van Dijk from Southampton in a club record £75m deal in the January transfer window.
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