Jurgen Klopp says he believes Virgil van Dijk is rediscovering his best form after struggling with injury for the most part of last year.
Anterior cruciate ligament damage ended the Dutchman's 2020/21 season early as Liverpool struggled with mass injuries, though he has returned to the starting XI this campaign as the Reds plot a Premier League title charge.
Speaking ahead of his side's clash with Leicester on Tuesday, Klopp said: "Virg has been really good, really good...long may it continue!
"It's like it is. The rehab worked really well, so he came back in really good shape. He needed some rhythm and it was important he got that rhythm.
"He's now back to his best, for sure. What helps us a lot - and what helps him a lot - is that we have options around so we don't have to push him through in the moments when his body is giving a sign that he needs to step aside for a moment. That's very helpful. That's why the situation is very good."
It's been four years since Liverpool splashed out £75m to sign Van Dijk from Southampton and the Anfield side have reaped the rewards from that investment, winning the Champions League and Premier League, and Klopp said that transfer was a pivotal moment for the club.
"Virgil's arrival was obviously a big day in our common history," Klopp added. "It is a good example for a winter transfer and how it works. A winter transfer works when you either wanted to sign a player the summer before or the summer after. That's the situation.
"We wanted Virgil in the summer [of 2017]; for some reasons we couldn't do the transfer at that moment but then in the winter we tried again and could get it through. It was a very important day, it changed a lot for us.
"In combination with Joel, with Dejan [Lovren], with Joey, we all of a sudden could defend in a different way. We could make the pitch smaller for the opponent so that was pretty helpful. That is why we are really happy."