The Reds signed the German shot stopper in a £4.7m deal from Bundesliga outfit Mainz in the 2016 summer transfer window.
Jurgen Klopp handed Karius the number one shirt in a clear show of support for the Germany Under-21 international.
However, the former Manchester City youth star made an uncertain start to his Anfield career and was dropped in favour of Simon Mignolet.
The Belgium international started the 2017-18 season as first-choice goalkeeper but Klopp has since reinstated Karius as his automatic starter.
The former Mainz goalkeeper has clearly made improvements to his game and has kept 11 clean sheets in his 22 games in all competitions this term.
However, Liverpool FC have been linked with a potential swoop to sign AS Roma goalkeeper Alisson Becker at the end of the season.
Karius conceded a penalty in the Reds’ 2-1 win at Crystal Palace in their last Premier League outing.
Former Reds captain Souness still has doubts about Karius despite his improvement in the current campaign.
“I question the goalkeeper at Liverpool,” Souness told Sky Sports. “Especially his decision making. He made a wrong decision that cost Liverpool a penalty [at Palace].”
Liverpool FC are in third place in the Premier League table and two points behind bitter rivals Manchester United in their bid to finish in second place.
The Reds signed Netherlands international Virgil van Dijk in the January transfer window.
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