The Reds signed the Scotland international in an £8m deal from Championship side Hull City in the 2017 summer transfer window.
The Merseyside outfit recruited Robertson to improve a problem position for the Reds ahead of the 2017-18 season.
Alberto Moreno started the season as Jurgen Klopp’s first-choice left-back before he suffered an injury in December.
Robertson stepped into the first team to create four assists in 19 games in the Premier League this term.
The 22-year-old started his first Champions League game in a 5-0 win against FC Porto last month.
Former Liverpool FC captain Redknapp spoke in glowing terms about Robertson following his impressive debut season at Anfield.
“What a signing he has been,” Redknapp told Sky Sports. “It was such a good ball across the goal.
“Liverpool have been trying to find a left back last year. They signed a young player from Hull. He has been brilliant.”
Liverpool FC are in third place in the Premier League table and two points adrift of runaway leaders Manchester City.
The Reds signed Virgil van Dijk in a £75m deal from Premier League rivals Southampton in the January transfer window.
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