The Guinea international moved to Liverpool FC in a £48m deal from Bundesliga side RB Leipzig in the 2018 summer transfer window.
Liverpool FC had agreed a transfer fee with the German club in 2017 but the Reds were forced to wait an additional 12 months before officially acquiring Keita.
The 23-year-old was handed his Liverpool FC debut in their Premier League opener and received rave reviews for his performance in a 4-0 win over West Ham United at Anfield.
Keita started their opening three Premier League games to help Liverpool FC make a 100 per cent start to the campaign before he was dropped to the bench for 2-1 win at Leicester in September.
The Guinea international has struggled with fitness problems over the past few months to limit Keita to one additional start, while the box-to-box midfielder has made a further five substitute appearances.
Mane, who moved to Liverpool FC in a £30m deal from Southampton in 2016, has backed Keita to mature into an important member of Klopp’s team.
“I always said, I knew Naby since Red Bull Salzburg because we played together. He is a great player and also young; he still has a lot to learn and improve,” Mane told Premier League Productions, as quoted by Liverpool FC’s website.
“When he came he surprised everyone but not me, because I know him. I’m sure he will do great things for us. Now he is back with the team and we are happy to have him. I’m looking forward to seeing him helping the team as he can.”
Keita was one of four signings in the summer transfer window, while Liverpool FC brought in AS Monaco midfielder Fabinho, AS Roma goalkeeper Alisson Becker and Stoke City playmaker Xherdan Shaqiri.
The Reds were 3-0 winners at Watford in the Premier League on Saturday afternoon.
Liverpool FC haven’t won the Premier League title but got their hands on the English top flight title in 1990 when Sir Kenny Dalglish was still in charge.
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