Liverpool are set to be without star men Luis Diaz and Diogo Jota, who have been sidelined with long-term injuries.
The strikers have already been out of action for some time, with Diaz picking up an injury in October before Jota was ruled out of the World Cup.
Jurgen Klopp will now have to restart the Premier League season without two key men who would boost their hopes of hunting down the top four.
How long is Luis Diaz out?
Diaz is expected to be out of action until March after suffering a setback in his recovery.
He picked up the injury in a 3-2 loss to Arsenal in October, ruling him out for the rest of the first half of the season.
Liverpool were then given hope of his return after two months out as he was included in their squad for their training camp in Dubai.
However, he was sent home shortly after Klopp revealed he had an incident in training.
The Reds boss said: “It’s definitely a big disappointment for all of us, for him too.
“It was a non-situation in training, honestly – nothing, felt something.
“I didn’t feel much the next day, but we wanted to be very careful and said, ‘OK, come on, let’s take a look.
Diaz is now set to undergo surgery on a lateral collateral ligament issue, extending his time out to a total of five months.
How long has Diogo Jota been out?
As for Jota, he is expected to be out until late January or early February.
The striker was stretched out in stoppage time at the Etihad Stadium against Man City after picking up a calf injury.
This forced him to miss the World Cup with Portugal when his place in the squad was all but certain.
He was also part of the Dubai training camp and Liverpool assistant coach Pep Lijnders gave an update on his condition.
“Jota is on schedule, he was with us in Dubai,” Lijnders said. “It’s good for a long-term injury that you can get out of this English weather, catch some sun and be with the team.
“He was with the team and he was still there but it’s the same amount of time [for return].”
The Reds are hoping to reunite with two of their key forwards as soon as possible, with their impact perhaps helping to reduce the 15-point deficit to league leaders Arsenal.
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