The midfielder picked up the injury during a challenge in Austria and has returned to Melwood to begin his rehabilitation with the club’s medical team.
Jürgen Klopp told Liverpoolfc.com: “Really unfortunate. An unfortunate situation as well; it was a challenge [in training].
“It looks like it is very similar to what Hendo had, which keeps him out for we don’t know for sure exactly how long, but for sure this pre-season he will not make a game, Arsenal for sure not and then we will see. The next game is probably two weeks later, but I don’t know.
“We have to wait but it is far away from being perfect, of course. It is really hard for him and hard for us, but it is not to change.”
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