Joël Matip is a doubt for Liverpool's clash with Arsenal on Friday despite a recent return to training, while Jürgen Klopp has revealed that Daniel Sturridge is struggling with illness.
Centre-back Matip has not featured in any of the Reds last five games since sustaining a thigh injury in a win at Stoke City last month and is nearing a return to full fitness, but could miss out on the trip to Emirates Stadium.
As could Sturridge, with the striker now ill after a tight hamstring had forced him to miss draws with Everton and West Bromwich Albion and Sunday's emphatic win over Bournemouth.
Klopp acknowledged that he is unsure whether Matip and Sturridge will be available in North London, but suggested the former will be back for the Boxing Day clash with Swansea City at Anfield.
The German insisted that Matip was back in training on Tuesday and added that the status of his squad is "how it is always" with "little reactions" and minor knocks from their previous game.
"We need to wait a little bit," he acknowledged, noting that "apart from" Sturridge, who is "a little bit ill" but "could be back", and their long-term absentees, he is "not sure" about who he will have available to face the Gunners.
Klopp continued: "But Joël Matip, it's positive. I'm not sure if he's ready for Arsenal, but [he will be] for the games coming up [after] then, I'm pretty sure. That's it, I think."
Reds keen to build up Lallana's "match fitness"
Midfielder Adam Lallana is also in contention to feature after a promising 20-minute cameo from the bench in their 4-0 victory over Bournemouth at the weekend.
That was just Lallana's second appearance of the season after a muscle injury kept him out until the end of November, and despite warning Liverpool must manage his return, Klopp says Lallana is ready to play again against Arsenal.
On the England international's display against the Cherries, Klopp joked that he was "aggressive" and that it was only "10 seconds or so until he had a yellow card."
The Reds boss declared that the news of Lallana's return is "good" but said he "needs to collect minutes now" and that Liverpool will see how they "manage that."
"He's not ready for three games, 90 minutes in a row, but he's ready to help us in specific moments," Klopp suggested, hinting that Lallana could come off the bench at Arsenal.
The manager said that Liverpool hope to "build up his match fitness step-by-step" and insisted that is "the only thing he's missing now."
Klopp felt that "even in the few minutes he was on the pitch, everybody could see what a player he is" and reiterated that it is "very good news" that Lallana is an option.
In addition to fitness doubts Matip and Sturridge, left-back Alberto Moreno remains out with an ankle injury he picked up against Spartak Moscow in the Champions League and Klopp said that the Spaniard is "still not even on the pitch" and that his comeback "could still take a few weeks."