Jurgen Klopp has confirmed Luis Diaz has suffered a fresh setback in his return from injury.
Colombian winger Diaz was forced to return home early from Liverpool's training camp in Dubai to have scans on his knee and will miss Sunday's friendly against Lyon. Diaz initially suffered the injury against Arsenal in October and only returned to training on Tuesday.
But Klopp had hoped he would return to action for the Reds when they get back to action against Manchester City in the Carabao Cup on December 22. "It's all good [fitness-wise] with the boys who are here," said Klopp, who has welcome the majority of the squad back from their World Cup break.
"What's not good is we have to see with Lucho [Diaz]. He felt something and we need to have further assessment there, but apart from that they all look really, really good."
Other than the World Cup stars, Diogo Jota is the only major absentee for Liverpool, with Joel Matip and Naby Keita building up their fitness in a bonus pre-season-type environment.
Klopp, whose side are sixth in the Premier League after a tough start, added: "It's a proper pre-season with different aspects because we were not together for two-and-a-half weeks, around about. But the boys had nine sessions in these two-and-a-half weeks just not with us, so it means the physical part is more or less done.
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"The training looks really good. It's high intense, we have long sessions and use each minute to get in the best possible shape, because we know we have a very intense second part of the season ahead of us.
"From a coaching point of view, it's really good fun to be together with them, to see them. We all want to strike back - that's the reality."
Liverpool return to Premier League action on Boxing Day - four days after their clash with City in the Carabao Cup. Klopp's side travel to Aston Villa before welcoming Leicester on December 30.
They currently sit four points behind Manchester United in the table and a further three off Tottenham in the coveted fourth spot. A title challenge seems unlikely already at this stage with leaders Arsenal 15 points ahead.
Despite their disappointing start, Klopp may feel optimistic his side can still have a successful campaign, with a Champions League last-16 tie to come against Real Madrid.
Welcoming back Diaz will be key to their hopes, as will the form of record-signing Darwin Nunez, who showed great improvement prior to the World Cup and was named as Liverpool's player of the month for November.
Nunez is set to be the first player involved in the World Cup to return to Liverpool training and could be involved in the friendly clash with AC Milan on December 16.
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