The England international has helped Southampton keep successive clean sheets in the Premier League against both Merseyside clubs.
The Saints managed to tame Jurgen Klopp’s free-scoring Liverpool attack in a goalless draw at St Mary’s earlier this month.
Bertrand was particularly impressed as Southampton eased to a 1-0 win against their former manager Ronald Koeman and his Everton side.
The 27-year-old moved to the Saints in a reported £10m deal from Chelsea in 2015 after a season-long loan at the south coast club.
The English defender scored two goals in 57 appearances for the west London side during a 10-year stay at Stamford Bridge dotted with loan spells.
Bertrand has already netted three times in 77 games in all competitions for Southampton since his initial loan move two-and-a-half seasons ago.
Former Liverpool and Southampton midfielder Redknapp heaped praise on Bertrand for having the courage to leave the west London outfit.
“Ryan Bertrand made a great move. He wasn’t getting his game at Chelsea. He looks a fantastic left-back,” Redknapp told Sky Sports.
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