The veteran midfielder has been a regular fixture in the first team at Anfield this term and has been earning plenty of praise for his strong performances for the Reds under Jurgen Klopp.
Milner has made has made 43 appearances in all competitions for Liverpool FC so far this season and has notched up 11 assists for his team-mates.
And Karius has been hugely impressed by what he has seen from the 32-year-old this term in a Liverpool FC shirt.
Speaking in an interview with Sky Sports, Karius said: “You can always rely on him [Milner], he’s so important.
“At the start of the season he came on from the bench and now he is starting pretty much every game.
“It’s fantastic to see how much he works for the team, he’s really needed. He does the dirty work for us.
“When you look after the game at how much running he does, it’s hard to believe he can do that every three or four days but he does. He’s like a machine, a really good player who is so important to us as a team.”
Milner and Karius helped Liverpool FC to book their place in the Champions League final following their aggregate victory over AS Roma in the semi-finals.
The Reds will take on Real Madrid in the Champions League final at the end of the month as they bid to finish the campaign on a high and win their first trophy under Klopp.
First though, Liverpool FC will look to cement a top-four finish in the Premier League as they prepare for their trip to Chelsea FC in the top flight on Sunday afternoon at Stamford Bridge.
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