The Reds signed Karius in a £4.7m deal from Bundesliga outfit Mainz 05 in the 2016 summer transfer window.
The German shot stopper was initially signed to improve the Liverpool FC goalkeeping options and dislodge Simon Mignolet.
However, Karius failed to take his chance in Jurgen Klopp’s team and Mignolet ended the 2016-17 season as first-choice.
But the German head coach restored his compatriot to his starting XI earlier this season and Karius hasn’t looked back.
The 24-year-old has managed to keep seven clean sheets in their last 11 games in all competitions.
Karius conceded one goal in a 5-1 win against Premier League leaders Manchester City in the Champions League quarter-finals.
Former Liverpool FC captain Redknapp believes Karius merits a starting spot in the Reds team for his outstanding performances.
“He has done well,” Redknapp told Sky Sports. “He deserves to be number one. Long term? Who knows!”
Liverpool FC haven’t won the Champions League since 2005 when the Reds beat Serie A giants AC Milan on penalties.
The Reds signed Virgil van Dijk in a £75m deal from Southampton in the January transfer window.
The 18-time English champions finished in fourth place in the Premier League table in his first full season in charge.
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