The midfielder has been an ever-present in the Premier League this season, forging a partnership with Lucas Leiva and helping the Reds to second in the table.
|5/4||Liverpool are 5/4 with BetVictor to finish in the Premier League top four|
"He has been playing fantastic like always. He's our captain and he's been really, really important for us," the left-back told reporters.
"When you get older, you lose something physically and, when he was playing with [Fernando] Torres, he was more behind the striker, making runs.
"Now he plays deeper, keeps more of the ball and works differently. He is playing with Lucas now in that sitting role, which he didn't play when he was younger.
"But the quality of the passes and the crosses he produces, and the free kicks ... at 50 years of age, he will still be doing the same thing! He will always have that and his quality is amazing."