Liverpool forward Luis Diaz is expected to be out for about three months after knee surgery.
The Colombia international experienced discomfort in the same area during Liverpool's current training camp in Dubai.
Liverpool manager Jurgen Klopp said earlier this week that Diaz's injury was "a proper smash in the face".
"It's clear it's a big disappointment for all of us, for him as well," he said.
"It was a non-situation in training - honestly, nothing - [but he] felt something. He didn't feel a lot next day but we wanted to be really cautious and said, 'Let's have a look'.